YOUR VOTE IS IMPORTANT

Whether or not you plan to attend the special meeting, please complete, sign and return the enclosed proxy card or submit your proxy by telephone or over the Internet following the instructions on the proxy card. If you hold your shares in "street name," you should instruct your broker how to vote in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. If you have any questions or need assistance, please call [    •    ], which is assisting us in our solicitation efforts, at [    •    ].

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CAUTIONARY NOTE TO UNITED STATES STOCKHOLDERS CONCERNING ESTIMATES OF MEASURED, INDICATED AND INFERRED RESOURCES

        The terms "mineral resource," "measured mineral resource," "indicated mineral resource" and "inferred mineral resource" that are used in this proxy statement are defined in Canadian National Instrument 43-101—Standards of Disclosure for Mineral Projects ("NI 43-101"). These Canadian terms are not recognized under Securities and Exchange Commission ("SEC") Industry Guide 7 and are normally not permitted to be used in reports and registration statements filed with the SEC by U.S. registered companies. Under SEC disclosure standards, mineralization may not be classified as a "reserve" unless the determination has been made that the mineralization could be economically and legally produced or extracted at the time the reserve determination is made. In addition, disclosure of "contained ounces" in a resource is permitted disclosure under Canadian regulations; however, the SEC normally only permits issuers to report mineralization that does not constitute "reserves" by SEC standards as in place tonnage and grade without reference to unit measures. Accordingly, stockholders are cautioned that the information contained in this proxy statement regarding ECU describing "mineral resources" is not directly comparable to information made public by U.S. companies subject to reporting requirements under U.S. securities laws. Stockholders are cautioned not to assume that any part or all of mineral deposits in these categories will ever be converted into reserves. "Inferred mineral resources" have a great amount of uncertainty as to their existence, and great uncertainty as to their economic feasibility. It cannot be assumed that all or any part of an inferred mineral resource will ever be upgraded to a higher category. Under Canadian rules, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies, except in rare cases. Investors are cautioned not to assume that all or any part of an inferred mineral resource exists or is economically minable.

CAUTIONARY STATEMENTS CONCERNING FORWARD-LOOKING INFORMATION

        Some information contained in or incorporated by reference into this proxy statement may contain forward-looking statements. These statements include statements in respect of the expected timing and anticipated benefits of the proposed business combination transaction between Golden and ECU (the "Transaction") and statements regarding future operations and activities of ECU, Golden or the combined company, including planned and potential exploration and development opportunities of the combined company, plans, expectations and assumptions concerning the El Quevar project or the Velardeña project, the timing and budget for exploration of our portfolio of exploration properties, our expected cash needs, and statements concerning our financial condition, operating strategies and operating and legal risks. There are also risks inherent in the nature of the proposed Transaction, including risks regarding the integration of the two entities, incorrect assessments of the values of the other entity, and failure to obtain the required securityholder, court, regulatory and other third party approvals.

        This proxy statement also includes forward-looking statements relating to the potential for further investment by The Sentient Group in the combined company. Golden and ECU caution investors that no agreement with respect to such further investment has been reached and provide no assurance that any such agreement will be reached.

        We use the words "anticipate," "continue," "likely," "estimate," "expect," "may," "could," "will," "project," "should," "believe" and similar expressions to identify forward-looking statements. Statements that contain these words discuss our future expectations, contain projections or state other forward-looking information. Although we believe the expectations and assumptions reflected in these forward-looking statements are reasonable, we cannot assure you that these expectations and assumptions will prove to be correct. The actual results of the combined company could differ materially from those expressed or implied in these forward-looking statements as a result of various risks, including the risk factors described in this proxy statement beginning on page [    •    ], the risk

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factors set forth in our annual report on Form 10-K, and the risk factors set forth in ECU's annual information form, including:

•

Results of future exploration at Golden's El Quevar project;



•

The feasibility and economic viability of potential expansion plans at ECU's Velardeña project;



•

The feasibility and economic viability of Golden's El Quevar project;



•

The combined company's ability to raise necessary capital to complete expansion plans at ECU's Velardeña project and if justified by results the development of Golden's El Quevar project;



•

The combined company's ability to retain key management and mining personnel necessary to successfully operate and grow our business;



•

Worldwide economic and political events affecting the market prices for silver and other minerals which may be found on our exploration properties; and



•

Political and economic instability in Argentina, Mexico, Peru, and other countries in which we conduct our business, and future actions of the governments in such countries with respect to nationalization of natural resources or other changes in mining or taxation policies.

        Many of those factors are beyond our ability to control or predict. You should not unduly rely on any of our forward-looking statements. These statements speak only as of the date of this proxy statement. Except as required by law, we are not obligated to publicly release any revisions to these forward-looking statements to reflect future events or developments. All subsequent written and oral forward-looking statements attributable to us and persons acting on our behalf are qualified in their entirety by the cautionary statements contained in this section and elsewhere in this proxy statement.

CONVERSION TABLE

        In this proxy statement, figures are presented in both metric and United States standard measurements. Conversion rates from United States standard to metric and metric to United States standard measurement systems are provided in the table below.

REPORTING CURRENCIES AND ACCOUNTING PRINCIPLES

        Unless otherwise indicated, all references to "$" or "dollars" in this proxy statement refer to United States dollars. References to "Cdn$" in this proxy statement refer to Canadian dollars. ECU's financial statements are reported in Canadian dollars and are prepared in accordance with Canadian GAAP (for periods prior to 2011) or IFRS (for 2011). Golden's financial statements that are incorporated by reference herein, as well as the pro forma financial statements included as Annex E to this proxy statement, are reported in U.S. dollars and are prepared in accordance with U.S. GAAP. Accordingly, in preparing the unaudited pro forma consolidated financial statements of the combined company as at and for the three months ended March 31, 2011, and the fiscal year ended December 31, 2010, as applicable, certain material adjustments were made in order to reconcile Canadian GAAP and IFRS with U.S. GAAP, as described in "Unaudited Pro Forma Condensed Combined Financial Statements" attached as Annex E.

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EXCHANGE RATES

        The following table sets forth (i) the noon rates of exchange for the Canadian dollar, expressed in Canadian dollars per U.S. dollar, in effect at the end of the period indicated, (ii) the average noon rates of exchange for such periods, and (iii) the high and low noon rates of exchange during such periods, in each case based on the noon rates of exchange as quoted by the Bank of Canada.

        On June 23, 2011, the last trading day before the announcement of the Transaction, the rate of exchange was $1.00 equals Cdn$0.9799, based on the noon rate of exchange as quoted by the Bank of Canada.

        On [    •    ], 2011, the rate of exchange was $1.00 equals Cdn$[    •    ] based on the noon rate of exchange as quoted by the Bank of Canada.

INFORMATION CONTAINED IN THIS PROXY STATEMENT

        The information contained in this proxy statement is given as of [    •    ], 2011 except where otherwise noted and except that information in documents incorporated by reference is given as of the dates noted therein.

        No person has been authorized by Golden to give any information or to make any representation in connection with the proposed business combination transaction or any other matters described herein other than as contained in this proxy statement and, if given or made, any such information or representation should be considered not to have been authorized by Golden or ECU.

        Certain information pertaining to ECU included or described herein (including financial statements of ECU) has been provided by or on behalf of ECU or is based on publicly available documents and records on file with the relevant Canadian provincial securities regulators and other public sources. Although Golden does not have any knowledge that would indicate that any such information is inaccurate or incomplete, Golden assumes no responsibility for the accuracy or completeness of such information, nor for the failure by ECU to disclose events which may have occurred or which may affect the completeness or accuracy of such information but which is unknown to Golden. Unless the context otherwise indicates, references in this proxy statement to "we," "our," "ours" and "us" refer to Golden and its subsidiaries, collectively.

        This proxy statement does not constitute the solicitation of an offer to purchase any securities or the solicitation of a proxy by any person in any jurisdiction in which such solicitation is not authorized or in which the person making such solicitation is not qualified to do so or to any person to whom it is unlawful to make such solicitation.

Information contained in this proxy statement should not be construed as legal, tax or financial advice and Golden stockholders are urged to consult their own professional advisors in connection with the proposed transaction.

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QUESTIONS AND ANSWERS ABOUT THE TRANSACTION AND THE SPECIAL MEETING

        The following questions and answers briefly address some commonly asked questions about the Transaction and the special meeting. You should carefully read this entire proxy statement, including the attached Annexes. Capitalized terms in this proxy statement have the meanings set out in the Glossary of Terms attached as Annex A or in the proxy statement.

Q:    What is Golden proposing?

A:

Golden stockholders are being asked to consider and vote upon two proposals. First, Golden stockholders will vote upon a proposal approving the issuance of Golden common stock in connection with a business combination transaction pursuant to which Golden will acquire all of ECU's outstanding common shares and convertible securities and ECU will become a wholly-owned subsidiary of Golden. The Transaction will be carried out pursuant to (i) an arrangement agreement dated June 24, 2011, between Golden and ECU, which we refer to as the "Arrangement Agreement," and (ii) a court-approved plan of arrangement under Chapter XVI—Division II of the Business Corporations Act (Québec), which we refer to as the "Plan of Arrangement." The Arrangement Agreement and Plan of Arrangement provide that ECU shareholders will receive 0.05 shares of Golden common stock and Cdn$0.000394 in cash for each ECU common share held immediately prior to the consummation of the Transaction. In addition, upon the consummation of the Transaction, new Golden options to purchase Golden common stock, or "Golden Replacement Options," will be exchanged for all outstanding options to purchase ECU common shares, and new Golden warrants to purchase Golden common stock, or "Golden Replacement Warrants," will be exchanged for all outstanding warrants to purchase ECU common shares. It is anticipated that consummation of the Transaction pursuant to the Plan of Arrangement will result in Golden paying an aggregate of approximately Cdn$125,000 in cash and issuing a total of approximately 16.0 million new shares, not including up to approximately 2.9 million new shares that will be issuable following the exercise of currently outstanding ECU options and warrants (or upon the exercise of the Golden Replacement Options and Golden Replacement Warrants to be received in exchange therefor).

In addition, Golden stockholders will vote upon a proposal to amend Golden's certificate of incorporation to increase the authorized number of shares of Golden common stock from 50,000,000 to 100,000,000. The approval of this proposal is not a condition to the closing of the Transaction.

Q:    How does the board of directors recommend that I vote?

A:

Golden's board of directors unanimously recommends that Golden's stockholders vote:

•

FOR the issuance of Golden common stock (including stock issuable upon exercise of Golden Replacement Options and the Golden Replacement Warrants) in connection with the Transaction, which we refer to as the "Share Issuance Proposal;" and

•

FOR the adoption of the amendment to Golden's certificate of incorporation to increase the authorized number of shares of Golden's common stock, which we refer to as the "Charter Amendment Proposal."

Q:    Why is Golden proposing to combine with ECU?

A:

Golden is proposing to combine with ECU because Golden believes that the Transaction will create a combined company with an attractive and more diversified portfolio of assets, greater scale and financial strength, and an enhanced capital markets profile. We believe that the combined company will be sufficiently capitalized to advance expansion plans at ECU's Velardeña

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project and the exploration of Golden's El Quevar project, and that combining the complementary management teams of the two companies will provide the broad experience and expertise necessary to lead these efforts. For additional information regarding ECU's Velardeña project and Golden's El Quevar project, see "Information Concerning ECU" and "Information Concerning Golden," beginning on pages [    •    ] and [    •    ], respectively.

Q:    Why is Golden proposing to amend its certificate of incorporation?

A:

Golden is proposing to amend its certificate of incorporation because, while an increase in authorized shares is not necessary to enable Golden to complete the Transaction, the increase will provide the Golden board with additional capacity to issue shares in future offerings or acquisitions following consummation of the Transaction as determined by Golden's board to be in the best interests of Golden's stockholders. The approval of the Charter Amendment Proposal is not a condition precedent to the consummation of the Transaction. Moreover, if the Share Issuance Proposal is not approved or the Transaction is not consummated for any reason, Golden will not amend its certificate of incorporation even if the Charter Amendment Proposal is approved.

Q:    Are there risks I should consider in deciding whether to vote for the Share Issuance Proposal?

A:

Yes. The Share Issuance Proposal and the Transaction are subject to a number of risks and uncertainties. Golden may not realize the benefits it currently anticipates from the Transaction due to the challenges associated with integrating the companies and other risks inherent in its mining business. See "Risk Factors" beginning on page [    •    ].

Q:    Am I entitled to dissenters' appraisal rights?

A:

No. Holders of Golden shares are not entitled to dissenters' appraisal rights in connection with the Transaction or any other action to be taken at the special meeting. See "General Information Concerning the Golden Meeting—Dissent Rights" beginning on page [    •    ].

Q:    How does Golden intend to finance the Transaction?

A:

The consideration to be paid by Golden in the Transaction consists primarily of Golden common stock. In addition, Golden will pay cash consideration of Cdn$0.000394 for each ECU share outstanding (an aggregate of approximately Cdn$125,000), with all such payments made from available cash on hand.

Q:    When do Golden and ECU expect to complete the Transaction?

A:

Golden and ECU expect to complete the Transaction when all of the conditions to completion of the Transaction have been satisfied or waived. The parties are working toward satisfying these conditions and completing the Transaction as quickly as possible. The parties currently plan to complete the Transaction on or about [    •    ] .

Q:    What is the role of Canadian courts with respect to the Transaction?

A:

Under the Business Corporations Act (Québec), a Québec court must approve the Plan of Arrangement. If ECU Securityholders approve the Transaction and Golden Stockholders approve the issuance of Golden common stock to be issued pursuant to the Transaction, the Superior Court of Québec will hold a hearing regarding a final order to approve the Plan of Arrangement and any amendments thereto made in accordance with the Arrangement Agreement. The court will consider, among other things, the fairness and reasonableness of the Plan of Arrangement. The court may approve the Plan of Arrangement in any manner and subject to compliance with such

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terms and conditions, if any, as the court may direct. The court's approval of the fairness of the Plan of Arrangement will serve as the basis for an exemption from the registration requirements of the United States Securities Act of 1933, as amended, or the "Securities Act," for the issuance of the Golden common stock, the Golden Replacement Options and the Golden Replacement Warrants to the ECU shareholders, optionholders and warrantholders, as applicable, in connection with the Plan of Arrangement and the Arrangement Agreement.

Q:    What will the share ownership, board of directors and management of Golden look like after the combination?

A:

We estimate that upon completion of the Transaction, former shareholders of ECU will own approximately 51% of the outstanding common stock of Golden, assuming that no outstanding ECU options or warrants are exercised before the consummation of the Transaction. If all of those options and warrants are exercised before the consummation of the Transaction, former securityholders of ECU will own approximately 55% of the outstanding stock of Golden. Upon consummation of the Transaction, we expect that we will expand the size of our board of directors in order to add one current ECU director, Michael T. Mason, to our board. In addition, it is our intention that ECU's current President, Stephen J. Altmann, will become the President of Golden after the Transaction. Golden's current Chairman and CEO, Jeffrey G. Clevenger, will retain these positions following the Transaction.

Q:    Why am I receiving this proxy statement?

A:

You are receiving this proxy statement and enclosed proxy card because, as of [    •    ], 2011, the record date for the special meeting, you owned shares of Golden common stock. Only holders of record of Golden common stock as of the close of business on [    •    ], 2011 will be entitled to vote those shares at the special meeting. Our board of directors is providing these proxy materials to give you information to determine how to vote in connection with the special meeting of our stockholders.

This proxy statement describes the proposals on which we would like you, as a stockholder, to vote. It also provides you with important information about these proposals to enable you to make an informed decision as to whether to vote your shares of Golden common stock to approve the matters described herein.

Your vote is very important and we encourage you to complete, sign, date and mail your proxy card, as soon as possible, whether or not you plan to attend the special meeting. Convenient telephone and Internet voting options are also available.

Q:    When and where is the special meeting?

A:

The special meeting will be held at [    •    ] on [    •    ], [    •    ], 2011 at [    •    ] Denver time.

Q:    What vote is required to approve the proposals?

A:

The Share Issuance Proposal must be approved by the affirmative vote of a majority of the shares of Golden common stock present at the special meeting and entitled to vote thereon, assuming a quorum is present.

The Charter Amendment Proposal must be approved by the affirmative vote of a majority of the outstanding shares of Golden common stock.

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Q:    What constitutes a quorum at the special meeting?

A:

The presence, in person or by proxy, of the holders of a majority of the outstanding shares of Golden common stock entitled to vote at the special meeting constitutes a quorum for the transaction of business at the special meeting. If you hold your shares through a broker or bank, and your broker or bank votes your shares on the Charter Amendment Proposal, those shares will be counted for purposes of determining the presence of a quorum at the meeting.

Q:    How many votes do I have?

A:

You have one vote for each share of Golden common stock that you own as of the record date.

Q:    How are votes counted?

A:

Votes will be counted by the inspector of election appointed for the special meeting, who will separately count "For" and "Against" votes, abstentions and broker non-votes. A "broker non-vote" occurs when a nominee holding shares for a beneficial owner does not receive instructions from the beneficial owner with respect to proposals relating to non-routine matters. The Share Issuance Proposal is considered a non-routine matter and the Charter Amendment Proposal is considered a routine matter.

Q:    How do I vote my Golden common stock?

A:

Before you vote, you should read this proxy statement in its entirety, including its Annexes, and carefully consider how the Transaction affects you. If you are a stockholder of record, you should mail your completed, dated and signed proxy card in the enclosed return envelope or submit your proxy by telephone or over the Internet as soon as possible so that your shares can be voted at the special meeting. For more information on how to vote your shares, see the section entitled "How You Can Vote."

If you hold your Golden common stock in "street name," you should follow the voting directions provided by your bank, brokerage firm or other nominee. You may complete and mail a voting instruction form to your bank, brokerage firm or other nominee or, in most cases, submit voting instructions by telephone or over the Internet to your bank, brokerage firm or other nominee. If you provide specific voting instructions by mail, telephone or the Internet, your bank, brokerage firm or other nominee will vote your shares of common stock as you have directed. Please note that if you wish to vote in person at the special meeting, you must obtain a "legal" proxy from your bank, brokerage firm or other nominee. If you do not provide your bank, brokerage firm or other nominee with voting instructions, your shares held through such entity will not be voted.

Q:    What happens if I do not vote?

A:

If you do not vote, your shares will not be counted toward the approval requirement for the Share Issuance Proposal. If you hold your shares through a broker, your broker may vote your shares on the Charter Amendment Proposal. Broker non-votes, if any, will have no effect on the Share Issuance Proposal but will have the same effect as a vote "AGAINST" the Charter Amendment Proposal. Abstentions will have the same effect as a vote "Against" the Share Issuance Proposal and the Charter Amendment Proposal.

Q:    What happens if I don't indicate how to vote on my proxy?

A:

If you are a record holder of Golden common stock and sign and send in your proxy card, but do not include instructions on how to vote, your shares will be voted "FOR" the Share Issuance Proposal and "FOR" the Charter Amendment Proposal. Golden's management does not currently

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intend to bring any proposals to the special meeting other than those described in this proxy statement. If other proposals requiring a vote of stockholders are properly brought before the special meeting, the persons named in the enclosed proxy card intend to vote the shares they represent in accordance with their best judgment.

Q:    What happens if I sell my shares of Golden common stock before the special meeting?

A:

The record date for stockholders entitled to vote at the special meeting is earlier than the date of the special meeting. If you transfer your shares of Golden common stock after the record date but before the special meeting, you will, unless special arrangements are made, retain your right to vote at the special meeting.

Q:    If my shares are held in "street name" by my broker, will my broker vote my shares for me?

A:

If your shares are held through a broker, bank or other nominee (collectively referred to as "brokers"), under applicable rules of NYSE Amex LLC ("NYSE Amex") (one of the exchanges on which our common stock is traded), the broker will vote your shares according to the specific instructions it receives from you. If the broker does not receive voting instructions from you, the broker may vote only on a proposal that is considered a "routine" matter under the NYSE Amex rules. At the special meeting, your broker may vote without your instructions only on the Charter Amendment Proposal, because it is considered a routine matter. Your broker may not vote on the Share Issuance Proposal because it is non-routine. The broker's failure to vote on the Share Issuance Proposal because it lacks discretionary authority to do so, commonly referred to as a "broker non-vote," will not affect the outcome of the vote on the Share Issuance Proposal. Any broker non-votes will have the same effect as a vote "AGAINST" the Charter Amendment Proposal.

Q:    Will my shares held in "street name" or another form of record ownership be combined for voting purposes with shares I hold of record?

A:

No. Because any shares you may hold in "street name" will be deemed to be held by a different stockholder than any shares you hold of record, shares held in "street name" will not be combined for voting purposes with shares you hold of record. Similarly, if you own shares in various registered forms, such as jointly with your spouse, as trustee of a trust or as custodian for a minor, you will receive, and will need to sign and return, a separate proxy card for those shares because they are held in a different form of record ownership. Shares held by a corporation or business entity must be voted by an authorized officer of the entity. Shares held in a retirement investment account must be voted under the rules governing the account.

Q:    What does it mean if I receive more than one set of materials?

A:

This means you own shares of Golden common stock that are registered under different names. For example, you may own some shares directly as a stockholder of record and other shares through a broker or you may own shares through more than one broker. In these situations, you will receive multiple sets of proxy materials. You must vote, sign and return all of the proxy cards or follow the instructions for any alternative voting procedure on each of the proxy cards that you receive in order to vote all of the shares you own. Each proxy card you receive comes with its own prepaid return envelope. If you vote by mail, make sure you return each proxy card in the return envelope that accompanies that proxy card.

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Q:    May I vote in person?

A:

Yes. You may attend the special meeting and vote your shares in person whether or not you sign and return your proxy card. If your shares are held of record by a broker, bank or other nominee and you wish to vote at the special meeting, you must obtain a "legal" proxy from the record holder.

Q:    May I change my vote after I have mailed my signed proxy card?

A:

Yes. You may revoke and change your vote at any time before your proxy card is voted at the special meeting. You can do this in one of three ways:

•

First, you can send a written notice to the Golden corporate secretary stating that you would like to revoke your proxy;

•

Second, you can complete and submit a new proxy in writing, by telephone or over the Internet; or

•

Third, you can attend the meeting and vote in person. Your attendance alone will not revoke your proxy.

If you have instructed a broker to vote your shares, you must follow directions received from your broker to change those instructions.

Q:    Who can help answer my questions?

A:

If you have questions about the Transaction and the special meeting, including the procedures for voting your shares, you should contact [    •    ] by telephone at [    •    ]. You may also call our proxy solicitor, [    •    ] , toll-free at [    •    ].

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SUMMARY

        The following information is a summary of certain information contained in this proxy statement. The information contained in this summary should be read in conjunction with, and is qualified in its entirety by, the more detailed information and financial data and statements contained elsewhere in this proxy statement, including the Annexes and the documents incorporated by reference. Capitalized terms in this Summary have the meanings set out in the Glossary of Terms attached as Annex A or as set out in this Summary.

The Transaction

        Golden and ECU are proposing to engage in a business combination transaction pursuant to which Golden will acquire all of the outstanding common shares, options and warrants of ECU, and ECU will become a wholly-owned subsidiary of Golden. The Transaction will be carried out pursuant to (i) the Arrangement Agreement dated June 24, 2011, between Golden and ECU, and (ii) a Court-approved arrangement under Chapter XVI—Division II of the Business Corporations Act (Québec), which we refer to as the "Plan of Arrangement". The Arrangement Agreement and Plan of Arrangement provide that ECU shareholders will receive 0.05 shares of Golden common stock and Cdn$0.000394 in cash for each ECU common share held immediately prior to the consummation of the Transaction. In addition, upon the consummation of the Transaction, new Golden options to purchase Golden common stock, or "Golden Replacement Options," will be exchanged for all outstanding options to purchase ECU common shares, and new Golden warrants to purchase Golden common stock, or "Golden Replacement Warrants," will be exchanged for all outstanding warrants to purchase ECU common shares. It is anticipated that consummation of the Transaction pursuant to the Plan of Arrangement will result in Golden paying an aggregate of approximately Cdn$125,000 in cash, and issuing a total of approximately 16.0 million new shares, not including up to approximately 2.9 million new shares that will be issuable following the exercise of currently outstanding ECU options and warrants (or upon the exercise of the Golden Replacement Options and Golden Replacement Warrants to be received in exchange for those options and warrants).

        See "The Transaction" beginning on page [    •    ].

The Arrangement Agreement

        Golden and ECU entered into the Arrangement Agreement on June 24, 2011. The terms and conditions of the Transaction are governed by the Arrangement Agreement. The Arrangement Agreement is attached to this proxy statement as Annex B and is part of this proxy statement. Golden urges you to read the Arrangement Agreement carefully as it is the legal document that governs the Transaction.

        See "The Arrangement Agreement" beginning on page [    •    ].

Parties to the Transaction

Golden Minerals Company

        Golden Minerals Company is a Delaware corporation headquartered in Golden, Colorado. We are a mineral exploration company with a diversified portfolio of precious metals and other mineral exploration properties located in or near the traditional precious metals producing regions of Mexico and South America. We are currently focused on advancement of our 100% controlled El Quevar silver project in northwestern Argentina and are engaged in additional drilling, metallurgical analysis and other advanced exploration work at El Quevar. In addition to El Quevar, we own and control a portfolio of approximately 45 exploration properties located primarily in Mexico and South America. Our 100% controlled Zacatecas silver and base metals project in Mexico is in an advanced stage of

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exploration, with six separate target areas on which we are currently conducting exploration activities, including drilling at the Adriana, San Manuel-San Gil, and the Pánuco targets. We also have reconnaissance properties on which we are conducting preliminary sampling and geological analysis to determine the best potential areas for more detailed exploration. Our principal offices are located in Golden, Colorado at 350 Indiana Street, Suite 800, Golden, CO 80401, and our telephone number is (303) 839-5060.

        See "Information Concerning Golden" beginning on page [    •    ] of this proxy statement.

ECU Silver Mining Inc.

        ECU Silver Mining Inc., a Québec corporation, is a Canadian-based mining company focused on the exploration, development and mining of silver, gold and base metals at its Velardeña District properties in Durango, Mexico. ECU owns and operates two mills with a combined capacity of 820 tonnes per day. ECU's executive offices are located at 87 Front Street East, 2nd Floor, Toronto, Ontario M5E 1B8, and its telephone number is (416) 366-2428.

        See "Information Concerning ECU" beginning on page [    •    ].

General Information Concerning the Golden's Stockholders Meeting

Date, Time and Place of the Meeting

        The Golden stockholders' vote will take place at a special meeting to be held at [    •    ] on [    •    ], [    •    ], 2011 at [    •    ] Denver time.

Record Date for Golden's Stockholders Meeting

        You are entitled to vote at the special meeting if you owned Golden common stock at the close of business on [    •    ], 2011.

Purpose of Golden Stockholder Meeting

        Golden's stockholders are being asked to consider and vote upon:

(i)

a proposal approving the issuance of shares of Golden common stock, par value $0.01 per share, (including stock issuable upon exercise of the Golden Replacement Options and Golden Replacement Warrants) in connection with the Transaction (this proposal is referred to as the "Share Issuance Proposal"); and



(ii)

a proposal to amend Golden's certificate of incorporation to increase the authorized number of shares of Golden common stock from 50,000,000 to 100,000,000 (this proposal is referred to as the "Charter Amendment Proposal").

        Approval of the Share Issuance Proposal is required to enable Golden to complete the Transaction. Approval of the Charter Amendment Proposal is not required to complete the Transaction. Approval of the Charter Amendment Proposal is being solicited in order to provide the Golden board with additional capacity to issue shares in future offerings or acquisitions following consummation of the Transaction as determined by the Golden board to be in the best interests of the Golden stockholders. See "General Information Concerning the Golden Meeting" beginning on page [    •    ].

Required Vote of Golden's Stockholders

        The Share Issuance Proposal must be approved by the affirmative vote of a majority of the shares of Golden common stock present at the special meeting and entitled to vote thereon, assuming a quorum is present. The Charter Amendment Proposal must be approved by the affirmative vote of a

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majority of the outstanding shares of Golden common stock. Abstentions will have the same effect as a vote "AGAINST" the Share Issuance Proposal and the Charter Amendment Proposal. Shares held through brokers may be voted without instruction by such brokers on the Charter Amendment Proposal but not the Share Issuance Proposal. A broker's failure to vote on the Share Issuance Proposal because it lacks discretionary authority to do so, commonly referred to as a "broker non-vote," will not affect the outcome of the vote on the Share Issuance Proposal.

Golden's Board Recommendation

        Golden's board of directors unanimously recommends that Golden's stockholders vote "FOR" the Share Issuance Proposal and "FOR" the Charter Amendment Proposal.

Opinion of Golden's Financial Advisor

        On June 23, 2011 Golden's board of directors received an opinion from BMO Capital Markets Corp. to the effect that, as of June 23, 2011, and subject to the various assumptions in the opinion, the exchange ratio, together with the cash consideration payable in the Transaction, was fair, from a financial point of view, to Golden.

        See "Fairness Opinion of Financial Advisor to Golden" beginning on page [    •    ].

Québec Court Approval

        Under the Business Corporations Act (Québec), the Transaction requires court and ECU securityholder approval. On July 14, 2011, ECU obtained an interim order from the Superior Court of Québec (the "Québec Court") providing for the calling and holding of the ECU special meeting and other procedural matters. Subject to receipt of the requisite approvals of the Transaction by securityholders of ECU and Golden at their respective special meetings, the hearing in respect of a final order from the Québec Court is expected to take place on or about August 31, 2011.

Anticipated Closing of the Transaction

        Golden and ECU will complete the Transaction when all of the conditions to completion of the Transaction have been satisfied or waived. The parties are working toward satisfying these conditions and completing the Transaction as quickly as possible. The parties currently plan to complete the Transaction on or about [    •    ], although there can be no assurance that the Transaction will be completed by this date, or at all.

Post-Transaction Governance

        Upon consummation of the Transaction, Golden plans to increase the size of its board of directors in order to add one current ECU director, Michael T. Mason, to the Golden board. In addition, ECU's current President, Stephen J. Altmann, is expected to become the President of Golden after the Transaction. Golden's current Chairman and CEO, Jeffrey G. Clevenger, will retain those positions in Golden following the Transaction.

        See "Directors and Officers of the Combined Company" beginning on page [    •    ].

U.S. Federal Income Tax Consequences

        There are no material U.S. federal income tax consequences to Golden's current stockholders that will result from Golden's acquisition of ECU or the issuance of Golden common stock pursuant to the Transaction.

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Private Placement Transaction

        On June 24, 2011, Golden and ECU entered into the subscription agreement, pursuant to which ECU issued to Golden on July 13, 2011 Cdn$15.0 million principal amount 0.0% senior unsecured convertible notes in a private placement. The private placement is intended to provide ECU with interim financing of its operations pending consummation of the Transaction. The convertible notes will mature on June 30, 2012 (subject to extension as described below), and will be convertible by Golden at any time prior to 5:00 p.m. (Toronto time) on June 29, 2012 into ECU Shares at the rate of 1,032 shares per Cdn$1,000 principal amount, consistent with the exchange ratio. The convertible notes will also be redeemable by ECU at any time after the record date for the special meeting of ECU Shareholders to approve the Transaction and prior to the maturity date, at 100% of the face value of the notes plus accrued and unpaid interest. ECU may elect to extend the maturity of the convertible notes to December 31, 2012 for a cash payment equal to 4% of the face value of the then outstanding notes, payable on the day the extension option is exercised, with interest accruing on the notes at 10% per annum during such extension period. Under the terms of the subscription agreement, the proceeds of the private placement are held in an escrow account and may be used only for certain specified purposes. As of July 13, the shares issuable upon conversion of the convertible notes represented approximately 4.7% of ECU's common shares outstanding on an as-converted basis.

        Golden, as holder of the convertible notes, is entitled to vote any ECU common shares received upon conversion of the Notes. Further, Golden may vote the convertible notes themselves in any vote of ECU's outstanding common shares, options, warrants and convertible securities voting as a single class, including with respect to the vote of ECU Securityholders to approve the Transaction. See "The Transaction—Subscription Agreement and Private Placement" on page [    •    ].

Risk Factors

        There are certain risk factors relating to Golden, ECU and the Transaction which should be carefully considered by stockholders, including the fact that the Transaction may not be completed if, among other things, Golden or ECU securityholder approval is not obtained, or if any other conditions precedent to the completion of the Transaction are not satisfied or waived, as applicable.

        See "Risk Factors" beginning on page [    •    ].

Pro Forma Financial Statements of the Combined Company

        See "Unaudited Pro Forma Condensed Combined Financial Statements" attached as Annex E.

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RISK FACTORS

        In addition to the other information contained in, or incorporated by reference into, this proxy statement (including the risk factors applicable to Golden contained under the heading "Risk Factors" in Golden's annual report on Form 10-K for the fiscal year ended December 31, 2010), the following factors should be considered carefully when considering risks related to the Transaction and the combined company. These risks and uncertainties are not the only risks Golden, ECU and the combined company may face, nor do they include all of the risks and uncertainties associated with the Transaction. If any such risks actually occur, the business, prospects, financial condition, cash flows and operating results of Golden, ECU and the combined company could be materially adversely affected. See "Where Stockholders Can Find More Information About Golden" beginning on page [    •    ] for a list of the documents incorporated by reference.

Risks Related to the Transaction

The Transaction will present challenges associated with integrating operations, personnel and other aspects of the companies and assumption of liabilities that may exist at ECU and which may be known or unknown by Golden.

        The results of the combined company following the Transaction will depend in part upon Golden's ability to integrate its business with ECU's business in an efficient and effective manner. Golden's attempt to integrate two companies that have previously operated independently may result in significant challenges, and Golden may be unable to accomplish the integration smoothly or successfully. In particular, the necessity of coordinating geographically dispersed organizations and addressing possible differences in corporate cultures and management philosophies may increase the difficulties of integration. ECU has operated as a Québec corporation, with substantially all of its personnel and operations in Mexico, and Golden has not previously conducted mining operations in Mexico. The integration will require the dedication of significant management resources to become familiar with the Mexican operations and the culture of ECU, which may temporarily distract management's attention from the day-to-day operations of the businesses of the combined company. In addition, the combined company may adjust the way in which ECU has conducted its operations and utilized its properties, which may require retraining and development of new procedures and methodologies. The process of integrating operations and making such adjustments after the Transaction could cause an interruption of, or loss of momentum in, the activities of one or more of the combined company's businesses and the loss of key personnel. Employee uncertainty, lack of focus or turnover during the integration process may also disrupt the businesses of the combined company. Any inability of management to integrate the operations of Golden and ECU successfully could have a material adverse effect on the business and financial condition of the combined company.

        In addition, the Transaction will subject Golden to any environmental, contractual or other obligations and liabilities of ECU, some of which may be unknown. While Golden and its legal and financial advisors have conducted due diligence on ECU and its business, there can be no assurance that Golden is aware of all obligations and liabilities of ECU. These liabilities, and any additional risks and uncertainties related to ECU's business and to the Transaction not currently known to Golden or that Golden may currently be aware of, but that prove to be more significant than assessed or estimated by Golden, could negatively impact the business, financial condition and results of operations of the combined company following consummation of the Transaction.

Golden will incur significant transaction, combination-related and restructuring costs in connection with the Transaction.

        Golden and ECU expect to incur transaction fees and other expenses related to the Transaction totaling approximately $12.0 million, including financial advisors' fees, filing fees, legal and accounting

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fees, soliciting fees, regulatory fees and mailing costs. ECU expects to incur costs for executive bonuses and change of control payments related to the Transaction totaling approximately Cdn$4.0 million. Golden also expects to incur significant costs associated with combining the operations of the two companies. It is difficult to predict the amount of these costs before Golden begins the integration process. The combined company may incur additional unanticipated costs as a consequence of difficulties arising from efforts to integrate the operations of the two companies. Although Golden expects that the elimination of duplicative costs, as well as the realization of other efficiencies related to the integration of the businesses, can offset incremental transaction, combination-related and restructuring costs over time, Golden cannot assure that this net benefit will be achieved in the near term, or at all.

The officers and directors of Golden and ECU may have interests that are different from the interests of Golden Stockholders.

        Because current stockholders of ECU will own 51% of the Golden common stock after the Transaction (55% on a fully diluted basis), the Transaction constitutes a change of control under several significant agreements to which Golden is a party, which triggers certain rights and obligations under those agreements. Unvested awards under Golden's 2009 Equity Incentive Plan (including stock options, restricted stock and restricted stock units) will vest immediately upon closing of the Transaction. At the closing of the Transaction, officers and directors of Golden will hold stock options to purchase 85,874 shares of common stock, and officers of Golden will hold 201,735 shares of restricted stock that would have vested on various dates between December 2011 and December 2013. Directors of Golden will hold 14,355 restricted stock units that would have vested during May 2012. In addition, Golden has change of control agreements with each of its executive officers that provide for severance benefits if, within two years of the closing of the Transaction, either the combined company terminates his or her employment without cause, or the officer terminates his or her employment for good reason. Although Golden does not currently anticipate that any such terminations will occur, if such terminations were to occur, Golden's executives would be entitled to receive severance payments consisting of cash, tax reimbursement, and perquisites equal to $[    •    ].

        In addition, ECU will make bonus payments for successful completion of the Transaction to its executive officers totaling Cdn$3.3 million (some of which may be paid in Golden common stock) and severance payments to certain of its officers upon closing the Transaction totaling approximately Cdn$0.7 million.

        These payments and potential benefits give the directors and management of Golden and ECU an interest in the Transaction that differs from the interest of Golden Stockholders.

Golden Stockholders will suffer immediate and substantial dilution to their equity and voting interests as a result of the issuance of Golden common stock to the ECU stockholders.

        In connection with the Transaction, Golden will issue approximately 16.0 million shares of common stock, which excludes up to 2.9 million new shares that will be issuable upon exercise of currently outstanding ECU warrants and options (or, following the Transaction, upon the exercise of the Replacement Options and Replacement Warrants issued in exchange for ECU warrants and options) and common stock expected to be issued in lieu of Cdn$2.75 million in transaction completion bonuses to Mr. Roy and Mr. Altmann. If all outstanding ECU options and warrants were exercised before the consummation of the Transaction, former ECU Shareholders would own approximately 55% of the outstanding stock of the combined company. Accordingly, the issuance of Golden common stock to ECU Shareholders will reduce the percentage of equity and voting interests held by each of Golden's current stockholders.

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        Golden has previously completed private placement transactions with Sentient Global Resources Fund III, LP and SGRF III Parallel I, LP (collectively, "Sentient") and Sentient has indicated a potential interest in further investing in the combined company in a private placement following consummation of the Transaction. The Transaction will increase the need of the combined company for additional financing to support the exploration and development of ECU's Velardeña properties in addition to Golden's historic properties. Because cash from operations is not expected to be sufficient to provide needed capital, and because debt financing is difficult to obtain for early stage mining operations, the likelihood is high that Golden would seek such financing in the equity markets. If the combined company were to engage in a private equity financing with Sentient or any other party, or engage in a public equity offering following the Transaction, current Golden Stockholders' ownership interest in the combined company would be further diluted.

Golden's common stock price could be depressed by sales of shares by ECU or Golden shareholders who sell their Golden shares.

        Some ECU Shareholders may intend not to hold Golden common stock and some Golden Stockholders may decide to sell their shares following the Transaction, particularly if the market reaction to the Transaction is not favorable. If a significant number of Golden or former ECU Shareholders seek to sell their Golden common stock following completion of the Transaction, the trading price of Golden common stock may be adversely affected. A decrease in the trading price of the Golden common stock could impair the combined company's ability to raise capital through future sales of common stock.

The existence of a significant number of options and warrants may have a negative effect on the market price of Golden common stock.

        ECU currently has outstanding ECU Options and ECU Warrants to purchase ECU Shares, which will, in the Transaction, be replaced by the Golden Replacement Options and Golden Replacement Warrants to purchase Golden common stock. The Golden Replacement Options will consist of employee options to purchase 661,750 shares of Golden common stock at exercise prices ranging from $16.00 to $31.80, and expiring between September 2011 and October 2014, and the Golden Replacement Warrants will consist of warrants to purchase 386,363 and 1,831,929 shares of Golden common stock, respectively, at exercise prices of $18.00 and $19.00, respectively, expiring in December 2011 and February 2014, respectively. The existence of securities available for exercise and resale is referred to as an "overhang", and, particularly if the options and warrants are "in the money", the anticipation of potential sales could exert downward pressure on the market price of Golden common stock.

Potential payments made to any dissenting ECU Shareholders in respect of their shares could exceed the amount of consideration otherwise due to them under the terms of the Arrangement Agreement.

        Under the Business Corporations Act (Québec), ECU Shareholders will have the right to dissent with respect to the proposed Transaction. If any ECU Shareholders properly exercise their right to dissent, such ECU Shareholders will be entitled to be paid the judicially determined fair value of their ECU Shares. While Golden and ECU believe that the value of the consideration to be paid to ECU Shareholders pursuant to the Transaction is equal to or exceeds the fair value of the ECU Shares, there can be no assurance that a court would agree with this assessment and consequently the amount any dissenting ECU Shareholders receive could be higher than the consideration to which those shareholders would have been entitled under the Arrangement Agreement. In addition, Golden may be required to pay dissenting ECU Shareholders all or a portion of the judicially determined value of their ECU Shares in cash, which would reduce the cash available to the combined company for advancement of the El Quevar project, expansion efforts at the Velardeña properties and advancement of the

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combined company's other exploration properties. A condition to closing in the Arrangement Agreement is that holders of no more than 5% of ECU's shares have exercised dissent rights, but Golden could waive this condition.

ECU's public filings are subject to Canadian disclosure requirements, which differ from SEC requirements.

        ECU is a Canadian issuer that is required to prepare and file its periodic and other filings in accordance with Canadian disclosure requirements. As a result, certain of the information about ECU that is contained in this proxy statement was prepared with a view to compliance with Canadian GAAP or IFRS and Canadian disclosure regulations, rather than the requirements that would apply in the United States. Because Canadian disclosure requirements are different from SEC requirements, the information about ECU contained in this proxy statement may not be comparable to similar information available about Golden or other U.S. issuers.

The presentation of historical financial statements of ECU will not be comparable to the presentation of ECU's financial results following completion of the Transaction.

        ECU has been a Québec corporation whose financial statements, until December 31, 2010, were prepared in accordance with Canadian GAAP, and since January 1, 2011, have been prepared in accordance with IFRS. After the Transaction, ECU will be a wholly-owned subsidiary of Golden, and its financial statements will be consolidated with those of Golden, and will be prepared in accordance with U.S. GAAP. Under Canadian GAAP and IFRS, ECU has been capitalizing exploration and development costs incurred during the development stage, including the operating expenses at its active mining operations, and offsetting those capitalized costs with revenue generated from saleable minerals. Under U.S. GAAP, those exploration and development costs would have appeared as expenses on the statement of operations and revenues generated during the development stage would have appeared as Other Income, Net of Incremental and Direct Costs Associated with the Revenue, on the statement of operations. If ECU had reported in U.S. GAAP for the fiscal year ended December 31, 2010, its net losses would have increased by approximately $2.5 million. Because of these and other differences, ECU's historical financial results will not be comparable to the results as they will appear in the consolidated financial statements of the combined company.

Risks Relating to the Businesses of Golden, ECU and the Combined Company

        After the completion of the Transaction, the business of the combined company, as well as the price of Golden common stock, will be subject to numerous risks currently affecting the businesses of Golden and ECU.

ECU and Golden have both historically incurred operating losses and operating cash flow deficits and we expect that the combined company will continue to incur operating losses in the foreseeable future.

        ECU and Golden have a history of operating losses and we expect that the combined company will continue to incur operating losses unless and until such time as ECU's Velardeña Properties in Central Mexico, our El Quevar project in Argentina, or another of our exploration properties generates sufficient revenue to fund continuing operations of the combined company. None of Golden's properties is currently in commercial production. While ECU is currently in production at its Velardeña Properties, it is still considered to be a development stage company, as it has not determined that a sufficient portion of its mineral resources are economically exploitable and, accordingly, it has no mineral reserves. We do not expect that revenues generated by production at ECU's properties will exceed the expenses of the combined company for at least the next few years. In 2010, ECU suffered a decrease in cash during the year of Cdn$7.3 million, leaving cash and cash equivalents of only $344,826 at December 31, 2010, and Golden has extended a $15.0 million interest-free convertible loan to ECU to provide it with needed liquidity pending the closing of the Transaction. We expect the combined

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company's operating expenses, capital expenditures and other expenses will increase in future years as we advance exploration, development and commercial production of the combined company's properties and any other properties that we may acquire. The amounts and timing of expenditures will depend on the progress of our efforts to expand production at the Velardeña Properties, advance our El Quevar project and continue exploration at these and other properties, the results of consultants' analyses and recommendations, the rate at which operating losses are incurred, the execution of any joint venture agreements with strategic partners, if any, and our potential future acquisition of additional properties, in addition to other factors, many of which will be beyond our control. We expect that the advancement or development of the combined company's properties and any other properties we may acquire will require the commitment of substantial resources. There can be no assurance that the combined company will continue to generate revenues or will ever achieve profitability.

ECU's and Golden's properties may not contain mineral reserves.

        None of our El Quevar project, ECU's Velardeña Properties or any of our other properties, has been shown to contain proven or probable mineral reserves. Expenditures made in the exploration and advancement of the properties of the combined company may not result in discoveries of commercially recoverable quantities of ore. Most exploration projects do not result in the discovery of commercially mineable ore deposits and we cannot assure you that any mineral deposit we identify will qualify as an ore body that can be legally and economically exploited or that any particular level of recovery of silver from discovered mineralization will in fact be realized.

        Micon has completed technical reports on Golden's El Quevar property, which indicated the presence of "mineralized material," and on ECU's Velardeña Properties, which indicated the presence of measured, indicated and inferred resources. Mineralized material, and measured, indicated and inferred resource figures based on estimates made by geologists are inherently imprecise and depend on geological interpretation and statistical inferences drawn from drilling and sampling that may prove to be unreliable or inaccurate. We cannot assure you that these estimates will be accurate or that proven and probable mineral reserves will be identified at El Quevar, Velardeña or any of Golden's and ECU's other properties. Even if the presence of reserves is established at a project, the economic viability of the project may not justify exploitation. We plan to spend significant amounts on the advancement of El Quevar and the expansion of the Velardeña Properties prior to establishing the economic viability of the project in a technical report compliant with NI 43-101.

        Estimates of reserves, mineral deposits and production costs can also be affected by such factors as governmental regulations and requirements, fluctuations in metals prices or costs of essential materials or supplies, environmental factors, unforeseen technical difficulties and unusual or unexpected geological formations. In addition, the grade of ore ultimately mined may differ from that indicated by drilling results, sampling, feasibility studies or technical reports. Short term factors relating to reserves, such as the need for orderly development of ore bodies or the processing of new or different grades, may also have an adverse effect on mining operations and on the results of operations. Silver or other minerals recovered in small scale laboratory tests may not be duplicated in large scale tests under on-site production conditions.

We expect that the combined company will continue to require substantial external financing to pay its operating and general and administrative expenses, continue the advancement of the Velardeña expansion and El Quevar projects, and fund its other exploration activities.

        We will be required to continue to raise substantial funds from external sources in order to pay our operating and general and administrative expenses, advance the Velardeña expansion and El Quevar projects, maintain our other exploration properties and continue our exploration activities, as we do not expect that cash generated by the Velardeña mining operations will be sufficient to fund these activities. If the Velardeña expansion or the El Quevar project proceeds to development and

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construction, we anticipate that we would need to raise additional capital during 2011. The size and capital cost for the Velardeña expansion or a possible mine and processing facilities at El Quevar have not been determined and would depend, among other things, on the results of our ongoing efforts to further define the Yaxtché deposit. We do not have a credit agreement in place that would finance development of either the Velardeña expansion or the El Quevar project, and believe that securing credit for these projects may be difficult given our limited history and the continuing volatility in global credit markets. Access to public financing has been negatively impacted by the volatility in the credit markets, which may impact the ability of the combined company to obtain equity or debt financing in the future and, if obtained, to do so on favorable terms. We cannot assure you that we will be able to obtain the necessary financing for the Velardeña expansion or the El Quevar project on favorable terms or at all. Failure to obtain sufficient financing may also result in the delay or indefinite postponement of exploration activities at our other properties.

The existence of secured indebtedness at ECU may limit the flexibility of the combined company to obtain additional financing and pursue certain business opportunities.

        Prior to the Transaction, Golden had no indebtedness. At June 30, 2011, ECU had approximately $17.0 million of outstanding term loan indebtedness, bearing interest at an effective rate of 12.8% and requiring 30 monthly principal repayments of $553,951, commencing July 31, 2011 through maturity on December 31, 2013. The term loan is secured by a first mortgage covering substantially all of ECU's assets, including its mining properties and mills. This indebtedness may be prepaid prior to maturity, subject to a prepayment penalty equal to the greater of either the total interest for the immediately preceding three months or 3% of the outstanding term loan principal amount. If such indebtedness had been prepaid on June 30, 2011, the prepayment penalty would have been $498,556. ECU refinanced this indebtedness in early 2011 to extend the maturity on the loan from January 2012 to December 2013.

        The presence of secured indebtedness, particularly in a company with limited revenues, has important consequences to the combined company, including (i) making it more difficult to obtain additional financing, (ii) subjecting it to the risk that its assets may be foreclosed upon if it is unable to make required principal and interest payments, (iii) reducing cash flows available for development of properties, and (iv) making the combined company more vulnerable than competitors without debt to a downturn in business, the economy or commodity prices. The combined company's ability to service its debt will depend on its operating performance, which is affected by prevailing economic conditions that are outside of its control. If it is unable to support debt service from revenues from ECU's mining operations, the combined company may be forced to divert resources from the development of its other properties, which may have material adverse effects on its growth and future prospects.

The ECU properties could be subject to environmental and other regulatory risks, which the combined company will assume after the Transaction and which could expose the combined company to significant liability and delay, and potentially the suspension or termination of exploration and development efforts.

        Mining is subject to federal, state and local environmental regulation in the jurisdictions where the mines are located. These regulations mandate, among other things, the maintenance of air and water quality standards and land reclamation. They also set forth limitations on the generation, transportation, storage and disposal of solid and hazardous waste.

        ECU's activities related to the Velardeña Properties are subject to regulation by SEMARNAT, the environmental protection agency of Mexico. Regulations require that an environmental impact statement, known in Mexico as a Manifestación de Impacto Ambiental, be prepared by a third-party contractor for submission to SEMARNAT. Studies required to support the Manifestación de Impacto Ambiental include a detailed analysis of soil, water, vegetation, wildlife, cultural resources and socio-economic impacts. The Manifestación is then published on SEMARNAT's web page and in its official

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gazette in a national and local newspaper. The Manifestación is discussed at various open hearings, including hearings in the local communities, at which third parties may voice their views. ECU is required to provide proof of local community support of the Manifestación as a condition to final approval. These requirements are applicable to permitting new facilities at ECU's operations and to expansion of ECU's existing facilities.

        Environmental legislation is evolving in a manner which will require stricter standards and enforcement, increased fines and penalties for non-compliance, more stringent environmental assessments of proposed projects, and a heightened degree of responsibility for companies and their officers, directors and employees. On January 28, 2011, Article 180 of the Mexican Federal General Law of Ecological Balance and Environmental Protection was amended. Among other things, this amendment extends the term during which an individual or entity having a legitimate interest may contest administrative acts, including environmental authorizations, permits or concessions granted, without the need to demonstrate the actual existence of harm to the environment, natural resources, flora, fauna or human health, making it sufficient to argue that the harm may be caused. Further, the amendment permits the contesting party to challenge a Manifestación de Impacto Ambiental through a variety of administrative or court procedures. As a result of the amendment, more legal actions supported or sponsored by non-governmental groups interested in halting projects may be filed against companies operating in all industrial sectors, including the mining sector. Mexican operations are also subject to the environmental agreements entered into by Mexico, the United States and Canada in connection with the North American Free Trade Agreement. Another initiative that has not yet been enacted, but is being analyzed by the Chamber of Deputies is one related to amendments to the Civil Federal Procedures Code ("CFPC"). This initiative consists of establishing three categories of collective actions, by means of which 30 or more people claiming injury resulting from, among other things, environmental harm, will be deemed to have a sufficient and legitimate interest in seeking, through a civil procedure, restitution, economic compensation or suspension of the activities from which the alleged injury derived. The initiative is expected to be approved by the Chamber of Deputies this year and the related provisions to become effective six months thereafter. If approved, the amendments to the CFPC may result in more litigation with plaintiffs seeking remedies, including suspension of the activities alleged to cause harm.

        Future changes in environmental regulation in the jurisdictions where the mines are located may adversely affect the operations of the combined company, make the operations of the combined company prohibitively expensive, or prohibit them altogether. Environmental hazards may exist on the properties in which Golden and ECU currently hold interests, or may hold interests in the future, that are unknown to Golden or ECU at present and that have been caused by Golden, ECU, or previous owners or operators, or that may have occurred naturally. The combined company may be liable for remediating any damage that ECU may have caused. The liability could include response costs for removing or remediating the release and damage to natural resources, including ground water, as well as the payment of fines and penalties.

        Insurance fully covering many environmental risks (including potential liability for pollution or other hazards as a result of disposal of waste products occurring from exploration and production) is not generally available. In addition, U.S. or international legislative or regulatory action to address concerns about climate change and greenhouse gas emissions could negatively impact the operations of the combined company.

Title to ECU Properties may be defective or may be challenged.

        Under the laws of Mexico, mineral resources belong to the state, and government concessions are required to explore for or exploit mineral reserves. Mineral rights derive from concessions granted, on a discretionary basis, by the Ministry of Economy, pursuant to the Mexican mining law and regulations thereunder. ECU holds title to the Velardeña Properties through these government concessions, but

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there is no assurance that title to the concessions comprising the Velardeña Properties will not be challenged or impaired following the Transaction. The Velardeña Properties may be subject to prior unregistered agreements, interests or native land claims, and title may be affected by undetected defects. There may be valid challenges to the title of any of the claims comprising the Velardeña Properties that, if successful, could impair development and/or operations with respect to such properties in the future. A defect could result in the combined company losing all or a portion of its right, title, and interest in and to the properties to which the title defect relates.

        ECU was previously involved in litigation concerning its ownership of title to four mineral concessions comprising the Santa Juana portion of the Velardeña Properties. In 2009, ECU entered into an agreement to settle the litigation whereby ECU agreed to pay $6.0 million to obtain full title to the concessions. ECU has previously paid $5.0 million of the settlement amount with the remaining $1.0 million installment becoming due in November 2011. Failure to make the remaining payment would result in loss of a 30% interest in the title to the four mining concessions at issue.

        Mining concessions in Mexico may be terminated if the obligations of the concessionaire are not satisfied, including obligations to explore or exploit the relevant concession, to pay any relevant fees, to comply with all environmental and safety standards, to provide information to the Ministry of Economy and to allow inspections by the Ministry of Economy. In addition to termination, failure to make timely concession maintenance payments and otherwise comply strictly with applicable laws, regulations and local practices relating to mineral right applications and tenure could result in reduction or expropriation of entitlements.

        Mining concessions give exclusive exploration and exploitation rights to the minerals located in the concessions, but do not include surface rights to the real property, such that ECU is required to negotiate the necessary agreements with surface landowners. Many of ECU's mining properties are subject to the Mexican ejido system requiring ECU to contract with the local communities surrounding the properties in order to obtain surface rights to land needed in connection with its mining operations or exploration activities. ECU's contract with the Velardeña Ejido, which provides surface rights to approximately 70% of the Velardeña Properties, expires in December 2011. Negotiations to renew the contract have not yet begun and while ECU expects to be able to obtain a new contract providing the same surface rights as the existing contract, no assurances can be made that ECU will be able to do so on favorable terms or at all. The inability to extend these surface rights on favorable terms or otherwise could have a material adverse effect on the operations and financial condition of the combined company.

ECU is actively engaged in mining activities and there are significant hazards involved, not all of which are fully covered by insurance. To the extent the combined company must pay the costs associated with such risks, its business may be negatively affected.

        The operation of mines and conduct of exploration programs are subject to numerous risks and hazards, including, but not limited to, environmental hazards, industrial accidents, encountering unusual or unexpected geological formations, formation pressures, cave-ins, fires, power outages, labor disruptions, flooding, seismic activity, rock bursts, accidents relating to historical workings, landslides and periodic interruptions due to inclement or hazardous weather conditions. These occurrences could result in damage to, or destruction of, mineral properties or production facilities, personal injury or death, environmental damage, reduced production and delays in mining, asset write-downs, monetary losses and possible legal liability. Although the combined company will maintain insurance against risks inherent in the operation of its business in amounts that it considers to be reasonable, such insurance will contain exclusions and limitations on coverage, the combined company's insurance will not cover all potential risks associated with mining and exploration operations, and related liabilities might exceed policy limits. As a result of any or all of the forgoing, particularly if the facilities are older, the

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combined company could incur significant liabilities and costs that could adversely affect its results of operation and financial condition.

ECU's mining operations are located in Mexico and are subject to various levels of political, economic, legal and other risks with which Golden has limited or no previous experience.

        ECU's operations are conducted in Mexico, and, as such, ECU's operations are exposed to various levels of political, economic, legal and other risks and uncertainties, including military repression; extreme fluctuations in currency exchange rates; high rates of inflation; labor unrest; the risks of war or civil unrest; local acts of violence, including violence from drug cartels; expropriation and nationalization; renegotiation or nullification of existing concessions, licenses, permits and contracts; illegal mining; acts of political corruption; changes in taxation policies; restrictions on foreign exchange and repatriation; and changing political conditions, currency controls and governmental regulations that favor or require the awarding of contracts to local contractors or require foreign contractors to employ citizens of, or purchase supplies from, a particular jurisdiction.

        In the past, Mexico has been subject to political instability, changes and uncertainties, which have resulted in changes to existing governmental regulations affecting mineral exploration and mining activities. Mexico's status as a developing country may make it more difficult for the combined company to obtain any required financing for the expansion of the Velardeña mines or other projects in Mexico in the future.

        ECU's Mexican operations and properties are subject to a variety of governmental regulations governing health and worker safety, employment standards, waste disposal, protection of historic and archaeological sites, mine development, protection of endangered and protected species and other matters. Specifically, ECU's activities related to the Velardeña Properties are subject to regulation by SEMARNAT, the environmental protection agency of Mexico, Comision Nacional del Agua, which regulates water rights, and Mexican mining laws. Mexican regulators have broad authority to shut down and/or levy fines against facilities that do not comply with regulations or standards.

        ECU's mineral exploration and mining activities in Mexico may be adversely affected in varying degrees by changing government regulations relating to the mining industry or shifts in political conditions that increase the costs related to ECU's Mexican operations or the maintenance of its properties. Changes, if any, in mining or investment policies or shifts in political attitude may adversely affect ECU's operations and financial condition. Operations may be affected in varying degrees by government regulations with respect to restrictions on production, price controls, export controls, currency remittance, income and other taxes, expropriation of property, foreign investment, maintenance of claims, environmental legislation, land use, land claims of local people, water use and mine safety. Expansion of ECU's facilities will also be subject to the need to assure the availability of adequate supplies of water and power, which could be affected by government policy and competing operations in the area.

        The occurrence of these various factors and uncertainties cannot be accurately predicted and could have an adverse effect on the combined company's operations and financial condition.

        Future changes in applicable laws and regulations or changes in their enforcement or regulatory interpretation could negatively impact current or planned exploration and development activities on the Velardeña Properties or in respect of any other projects in which the combined company becomes involved in Mexico. Any failure to comply with applicable laws and regulations, even if inadvertent, could result in the interruption of exploration and development operations or material fines, penalties or other liabilities.

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ECU's employees in Mexico are represented by a collective bargaining unit, and ECU is subject to Mexican regulations regarding labor and employment matters.

        ECU's employees in Mexico are represented by a collective bargaining unit, the Sindicato. ECU has two Sindicatos, one for the mine and a second for the plant. The current collective bargaining agreement expired in late June 2011. Salaries are negotiated annually, and labor contracts bi-annually. In addition to the negotiated terms of such agreement, relations between ECU and its employees may be affected by changes in regulations regarding labor relations that may be introduced by the Mexican authorities. Changes in such legislation or in the relationship between ECU and its employees may have a material adverse effect on the combined company's operations and financial condition.

The long-term cash flow and profitability of the combined company will be affected by changes in the prices of silver and other metals.

        The ability of the combined company to establish reserves and develop its exploration properties, and its profitability and long-term viability, depend, in large part, on the market prices of silver, zinc, lead, gold, copper and other metals. The market prices for these metals are volatile and are affected by numerous factors beyond our control, including:

•

global or regional consumption patterns;



•

supply of, and demand for, silver, gold, zinc, lead, copper and other metals;



•

speculative activities and producer hedging activities;



•

expectations for inflation;



•

political and economic conditions; and



•

supply of, and demand for, consumables required for production.

        Future weakness in the global economy could increase volatility in metals prices or depress metals prices, which could in turn reduce the cash flow generated by the Velardeña Properties, or make it uneconomical for the combined company to continue its mining or exploration activities. Volatility or sustained price declines may also adversely affect the ability of the combined company to build its business.

Results from ECU's Velardeña properties are subject to exchange control policies, the effects of inflation and currency fluctuations between the U.S. Dollar and the Mexican Peso.

        ECU's revenues are primarily denominated in U.S. dollars. However, operating costs of ECU's Velardeña Properties are denominated principally in Mexican pesos. These costs principally include electricity, labor, maintenance, local contractors and fuel. Accordingly, when inflation in Mexico increases without a corresponding devaluation of the Mexican peso, ECU's financial position, results of operations and cash flows could be adversely affected. The annual inflation rate in Mexico was 4.4% in 2010, 3.6% in 2009 and 6.5% in 2008. At the same time, the peso has been subject to significant devaluation, which may not have been proportionate to the inflation rate and may not be proportionate to the inflation rate in the future. The value of the peso increased by 5.4% and 3.5% in 2010 and 2009, respectively, and decreased by 24.5% in 2008. In addition, fluctuations in currency exchange rates may have a significant impact on our financial results. There can be no assurance that the Mexican government will maintain its current policies with regard to the peso or that the peso's value will not fluctuate significantly in the future. The imposition of exchange control policies could impair ECU's ability to meet its U.S. dollar-denominated obligations, including payments on its debt. We cannot assure you that currency fluctuations, inflation and exchange control policies will not have an adverse impact on the financial condition, results of operations, earnings and cash flows of the combined company.

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If the combined company is unable to obtain all of its required governmental permits or obtain property rights on favorable terms or at all, its operations could be negatively impacted.

        Future operations of the combined company, including the new tailings facility at and potential expansion of the Velardeña Properties, the advancement of the El Quevar project, and other exploration and potential development activities, will require additional permits from various governmental authorities. Operations of the combined company are and will continue to be governed by laws and regulations governing prospecting, development, mining, production, exports, taxes, labor standards, occupational health, waste disposal, toxic substances, land use, environmental protection, mine safety, mining royalties and other matters. The combined company may also be required to obtain certain property rights to access or use its properties. Obtaining or renewing licenses and permits, and acquiring property rights, can be complex and time-consuming processes. There can be no assurance that the combined company will be able to acquire all required licenses, permits or property rights on reasonable terms or in a timely manner, or at all, and that such terms will not be adversely changed, that required extensions will be granted, or that the issuance of such licenses, permits or property rights will not be challenged by third parties. Delays in obtaining or a failure to obtain any licenses, permits or property rights or any required extensions; challenges to the issuance of licenses, permits or property rights, whether successful or unsuccessful; changes to the terms of licenses, permits or property rights; or a failure to comply with the terms of any licenses, permits or property rights that have been obtained, could have a material adverse effect on the business of the combined company by delaying or preventing or making continued operations economically unfeasible.

ECU owns its interest in its San Diego property in a 50-50 joint venture and is therefore unable to control all aspects of exploration and development of this property.

        ECU holds the San Diego property in a 50-50 joint venture with Golden Tag Resources Ltd. This interest in the San Diego Property is subject to the risks normally associated with the conduct of joint ventures. A disagreement between joint venture partners on how to conduct business efficiently, the inability of joint venture partners to meet their obligations to the joint venture or third parties, or litigation arising between joint venture partners regarding joint venture matters could have a material adverse effect in the viability of ECU's interests held through the joint venture. In 2009, ECU received a notice of arbitration from its joint venture partner. The dispute was settled in September 2010, and resulted in an increase in ECU's mining property costs of $61,000.

Risks Related to the Increase in Authorized Capital.

The increase in authorized capital could have anti-takeover effects, and could lead to greater dilution to existing stockholders.

        Stockholders are being asked to approve an increase in Golden's authorized capital from 50,000,000 shares to 100,000,000 shares. At the conclusion of the Transaction, Golden will have approximately 12.7 million shares available for issuance. The additional shares will be available for use in acquisitions, future equity financings and for employee equity compensation plans. If the Charter Amendment Proposal is approved, Golden Stockholders will not have the ability in the future to vote on the use of the shares, except in limited instances mandated by stock exchange rules. Accordingly, the directors would be able to issue shares in financings or acquisitions at prices that may not reflect market prices, or are otherwise dilutive to stockholders. In addition, the availability of a number of authorized and unissued shares could have anti-takeover effects and could be used by incumbent management to perpetuate its positions, even in the face of an acquisition that is regarded as beneficial by stockholders. For example, shares could be placed with a stockholder that is supportive of existing management, diluting the ownership of a hostile acquirer. There can be no assurance that the shares will be issued in a manner that is advantageous to existing stockholders.

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GENERAL INFORMATION CONCERNING THE GOLDEN MEETING

        The enclosed proxy is solicited on behalf of Golden's board of directors for use at a special meeting of Golden's stockholders to be held on [    •    ], 2011, at [    •    ] Denver time, or at any adjournments, postponements or delays thereof, for the purposes set forth in this proxy statement and in the accompanying notice of special meeting. The special meeting will be held at [    •    ]. Golden intends to commence mailing of this proxy statement and the accompanying proxy card to Golden's stockholders on or about [    •    ], 2011.

        At the special meeting, Golden's stockholders will be asked to vote on:

•

Share Issuance Proposal—the issuance of shares of Golden common stock (including shares issuable upon exercise of Golden Replacement Options and Golden Replacement Warrants) in connection with the Transaction; and



•

Charter Amendment Proposal—an amendment to Golden's certificate of incorporation to increase the authorized number of shares of Golden common stock from 50,000,000 to 100,000,000.

        Golden does not expect a vote to be taken on any other matters at the special meeting. If any other matters are properly presented at the special meeting for consideration, however, the holders of the proxies will have discretion to vote on these matters in accordance with their best judgment.

        Golden's board of directors has unanimously approved the Transaction and the issuance of Golden common stock in connection with the Transaction. In addition, our board has determined that an increase in the authorized number of shares of Golden common stock is advisable in order to provide the Golden board additional capacity to issue shares in the future, including for future offerings or acquisitions as determined to be in the best interests of the Golden stockholders. Accordingly, the board of directors unanimously recommends that Golden's stockholders vote "FOR" the Share Issuance Proposal and "FOR" the Charter Amendment Proposal.

        Only approval of the Share Issuance Proposal is required to effect the Transaction. If the Charter Amendment Proposal is approved but the Share Issuance Proposal is not approved, Golden will not amend its certificate of incorporation to increase the authorized number of shares of Golden common stock. Golden stockholders will cast separate votes on each proposal.

        There are certain risks associated with the Transaction, which are described under the heading "Risk Factors," beginning on page [    •    ].

Record Date and Voting Information

        Only holders of record of Golden common stock at the close of business on [    •    ], 2011 are entitled to notice of and to vote at the special meeting. At the close of business on [    •    ], 2011, [    •    ] shares of Golden common stock were outstanding and entitled to vote. A list of Golden's stockholders will be available for review at Golden's executive offices during regular business hours after the date of this proxy statement and through the date of the special meeting. Each holder of record of Golden common stock on the record date will be entitled to one vote for each share held. The presence, in person or by proxy, of the holders of a majority of the outstanding shares of Golden common stock entitled to vote at the special meeting is necessary to constitute a quorum for the transaction of business at the special meeting.

        All votes will be tabulated by the inspector of election appointed for the special meeting, who will separately tabulate votes "FOR" and "AGAINST," abstentions and broker non-votes. If a stockholder's shares are held of record by a broker, bank or other nominee and the stockholder wishes to vote at the special meeting, the stockholder must obtain from the record holder a "legal" proxy issued in the stockholder's name. Brokers who hold shares in "street name" for clients typically have the authority to

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vote on "routine" proposals when they have not received instructions from beneficial owners. Absent specific instructions from the beneficial owner of the shares, brokers are not allowed to exercise their voting discretion with respect to the approval of "non-routine" matters, such as the Share Issuance Proposal. Broker non-votes are counted for purposes of determining whether a quorum exists at the special meeting.

        Proxies received at any time before the special meeting and not revoked or superseded before being voted will be voted at the special meeting. If the proxy indicates a specification, it will be voted in accordance with the specification. If no specification is indicated, the proxy will be voted "FOR" the Share Issuance Proposal and "FOR" the Charter Amendment Proposal, and in the discretion of the persons named in the proxy with respect to any other business that may properly come before the special meeting or any adjournment of the special meeting. You may also vote in person by ballot at the special meeting.

Required Vote of Golden's Stockholders

        The Share Issuance Proposal must be approved by the affirmative vote of a majority of the shares of Golden common stock present at the special meeting and entitled to vote, assuming a quorum is present. The Charter Amendment Proposal must be approved by the affirmative vote of a majority of the outstanding shares of Golden common stock. Abstentions will have the same effect as a vote "AGAINST" the Share Issuance Proposal and the Charter Amendment Proposal. Shares held through brokers may be voted by the brokers on the Charter Amendment Proposal but not the Share Issuance Proposal. A broker's failure to vote on the Share Issuance Proposal because it lacks discretionary authority to do so, commonly referred to as a "broker non-vote," will not affect the outcome of the vote on the Share Issuance Proposal.

Golden's Board Recommendation

        Golden's board of directors unanimously recommends that Golden's stockholders vote "FOR" the Share Issuance Proposal and "FOR" the Charter Amendment Proposal.

Opinion of Golden's Financial Advisor

        On June 23, 2011 Golden's board of directors received an opinion from BMO Capital Markets Corp. to the effect that, as of June 23, 2011, and based upon and subject to the factors, assumptions, qualifications and limitations set forth in such opinion, the exchange ratio, together with the cash consideration to be paid by Golden pursuant to the Transaction, was fair, from a financial point of view, to Golden.

How You Can Vote

        Each share of Golden common stock outstanding on [    •    ], 2011, the record date for stockholders entitled to vote at the special meeting, is entitled to vote at the special meeting. On the record date, [    •    ] shares of Golden common stock were issued and outstanding.

        If you are a record holder, you may vote your shares in any of the following ways:

        Voting by mail.    If you choose to vote by mail, simply mark your proxy, date and sign it, and return it in the postage-paid envelope provided.

        Voting by telephone.    You can vote your proxy by telephone by calling the toll free number [    •    ]. You will then be prompted to enter the control number printed on your proxy card and to follow the subsequent instructions. Voting by telephone is also available 24 hours a day. If you vote by telephone, do not return your proxy card(s).

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        Voting by Internet.    You can also vote your proxy via the Internet. The website for Internet voting is www.[    •    ], and voting is also available 24 hours per day. If you vote via the Internet, you should not return your proxy card(s). Instructions on how to vote via the Internet are located on the proxy card enclosed with this proxy statement. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and create an electronic voting form.

        Voting in Person.    You can also vote by appearing and voting in person at the special meeting.

        You should return a proxy by mail, by telephone, or via the Internet even if you plan to attend the special meeting in person.

        If you are a beneficial owner of common stock held in "street name," you will receive instructions from your bank, brokerage firm or other nominee that you must follow in order to have your shares of Golden common stock voted. Those instructions will identify which of the above choices are available to you in order to have your shares voted. Please note that if you are a beneficial owner of common stock and wish to vote in person at the special meeting, you must obtain a "legal" proxy from your bank, brokerage firm or other nominee.

Proxies; Revocation

        Any person giving a proxy pursuant to this solicitation has the power to revoke and change it anytime before it is voted. It may be revoked and/or changed at any time before it is voted at the special meeting by:

•

giving written notice of revocation to Golden's Corporate Secretary;



•

submitting another proper proxy via the Internet, by telephone, or a later-dated written proxy; or



•

attending the special meeting and voting by paper ballot in person. Your attendance at the special meeting alone will not revoke your proxy.

        If you hold your Golden common stock in "street name," you should contact your bank, brokerage firm or other nominee for instructions regarding how to change your vote. You may also vote in person at the special meeting if you obtain a "legal" proxy from your bank, brokerage firm or other nominee.

Shares Beneficially Owned by Golden Directors and Executive Officers

        On the record date, Golden directors and named executive officers beneficially owned and had the right to vote approximately [    •    ] million Golden shares. These shares represent, in the aggregate, approximately [    •    ] % of the total voting power of Golden's outstanding common stock entitled to vote at the special meeting. On [    •    ], 2011, ECU entered into voting agreements with each of Golden's directors and executive officers. Pursuant to these voting agreements, the Golden directors and officers party to such agreements committed to vote their shares of Golden common stock in support of the Transaction. See "The Transaction—Voting Agreements" beginning on page [    •    ] for a further description of the voting agreements.

Expenses of Proxy Solicitation

        Golden will pay the costs of soliciting proxies for the special meeting. Officers, directors and employees of Golden may solicit proxies by telephone, mail, the Internet or in person. However, they will not receive extra compensation for soliciting proxies. Golden will also request that individuals and entities holding shares in their names, or in the names of their nominees, that are beneficially owned by others, send proxy materials to and obtain proxies from, those beneficial owners, and will reimburse those holders for their reasonable expenses in performing those services. [    •    ] has been retained by Golden to assist it in the solicitation of proxies, using the means referred to above, and will receive a

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$[    •    ] retainer plus a fee based upon its standard hourly rates, plus reimbursement of out-of-pocket expenses.

Dissent Rights

        Under applicable Delaware laws and U.S. securities laws, Golden stockholders are not entitled to dissenters' appraisal rights in connection with the Transaction or any other matters to be acted upon at the Golden special meeting.

Adjournments

        Although it is not expected, the special meeting may be adjourned for any reason by the chairman of the meeting. If a quorum is not present at the special meeting, the meeting may be adjourned by the chairman or the stockholders present at the meeting. When a meeting is adjourned to another time and place, if any, notice need not be given of the adjourned meeting if the date, time and place, if any, by which stockholders and proxy holders may be deemed to be present in person and vote at such adjourned meeting are announced at the meeting. If, however, the adjournment is for more than 30 days, or if a new record date is fixed for the adjourned meeting, a notice of the adjourned meeting must be provided to each stockholder entitled to vote at the adjourned meeting. Such notice will be mailed or transmitted electronically to you and will be provided not less than 10 days nor more than 60 days before the date of the adjourned meeting and will set forth the purpose of the meeting. In addition, in accordance with applicable law, Golden may postpone the special meeting to another time, date, or place.

Other Matters

        Golden's board of directors is not aware of any business to be brought before the special meeting other than that described in this proxy statement.

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THE TRANSACTION

General

        On June 24, 2011, Golden and ECU entered into the Arrangement Agreement, which sets forth the terms under which Golden will acquire all of the ECU Shares, ECU Options and ECU Warrants in accordance with the Plan of Arrangement to be submitted for approval by the Québec Court. Pursuant to the Arrangement Agreement, Golden will acquire all the ECU Shares pursuant to the Plan of Arrangement in exchange for Golden common stock and cash.

        The Arrangement Agreement and Plan of Arrangement provide that ECU shareholders will receive 0.05 shares of Golden common stock and Cdn$0.000394 in cash for each ECU common share held immediately prior to the consummation of the Transaction. In addition, upon the consummation of the Transaction, new Golden options to purchase Golden common stock, or "Golden Replacement Options," will be exchanged for all outstanding options to purchase ECU common shares, and new Golden warrants to purchase Golden common stock, or "Golden Replacement Warrants," will be exchanged for all outstanding warrants to purchase ECU common shares. It is anticipated that consummation of the Transaction pursuant to the Plan of Arrangement will result in Golden paying an aggregate of approximately Cdn$125,000 in cash and issuing a total of approximately 16.0 million new shares, not including up to approximately 2.9 million new shares that will be issuable following the exercise of currently outstanding ECU options and warrants (or upon the exercise of the Golden Replacement Options and Golden Replacement Warrants to be received in exchange for those options and warrants).

Background of the Transaction

        Golden's management and board of directors routinely monitor and assess developments in the mining and exploration industries and regularly consider growth opportunities, including the acquisition of operating mines, exploration properties and businesses.

        On January 11, 2011, Mr. Jeffrey G. Clevenger, Chairman, President and Chief Executive Officer of Golden, and Jerry Danni, Executive Vice President of Golden, met in New York with representatives of Dahlman Rose & Company, an investment banking firm which specializes in the mining industry. Among other issues related to industry developments and strategic considerations, the representatives of Dahlman Rose stated that they had been engaged by ECU to pursue strategic alternatives and discussed with Mr. Clevenger and Mr. Danni the possibility of a strategic investment in or combination with ECU. Following this meeting, representatives of Dahlman Rose provided Mr. Clevenger and Mr. Danni with certain publicly available information regarding ECU. Representatives of Dahlman Rose conducted another informal discussion regarding ECU with Mr. Danni on March 8, 2011, at the Prospectors and Developers Association of Canada annual conference in Toronto.

        In late March 2011, Golden management commenced a review, based on public information, of several potential acquisition targets and strategic business combination partners, including ECU. The preliminary analysis of ECU was completed during the first week of April 2011. On April 4, 2011, Mr. Clevenger asked a representative of Dahlman Rose to arrange an introductory meeting with appropriate ECU executives.

        On April 13, 2011, Mr. Clevenger and Mr. Danni met with Stephen Altmann, President of ECU, and representatives of Dahlman Rose in Zurich, Switzerland, where they were attending the annual meeting of the European Gold Forum. At this meeting, Messrs. Clevenger, Danni and Altmann provided general overviews of their companies based solely on publicly available information. They discussed the possibility of a strategic business combination and whether each party was interested in pursuing further discussions. Messrs. Clevenger, Danni and Altmann concluded the meeting with an

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agreement to continue preliminary discussions and to enter into a confidentiality agreement in respect of the planned discussions.

        Golden management and ECU management then negotiated a mutual confidentiality agreement, which was executed on April 21, 2011. The confidentiality agreement included a two year "standstill" agreement under which each of Golden and ECU agreed not to propose a takeover or business combination transaction to the other or its stockholders without the consent of the other's board of directors. During this period, Mr. Clevenger and Mr. Altmann spoke by telephone and communicated by email regarding the coordination of initial due diligence activities, including travel to ECU's Velardeña District properties in Mexico and Golden's El Quevar advanced exploration project in Argentina.

        On April 27, 28 and 29, 2011, David Drips, Golden's Project Director, Argentina, and Mr. Robert Blakestad, Golden's Senior Vice President and Chief Geologist, conducted on-site due diligence at ECU's Velardeña District mines, processing facilities and properties and received information regarding mining, processing, geology, ore controls, exploration and potential areas for additional discovery.

        On May 2, 2011, ECU provided Golden with preliminary technical data and corporate information.

        On May 9 and 10, 2011, Mr. Clevenger had discussions by telephone with representatives of BMO Capital Markets regarding its acting as Golden's financial advisors and requested BMO Capital Markets to serve as its financial advisor in connection with a potential business combination transaction with ECU.

        On May 10, 11 and 12, 2011, Messrs. Clevenger and Drips conducted additional on-site due diligence of the Velardeña mines, properties and processing facilities. In addition, on May 11, 2011, Mr. Clevenger, Mr. Altmann and Mr. Michel Roy, Chairman and Chief Executive Officer of ECU, discussed their views regarding the potential strategic and financial benefits of a business combination transaction between Golden and ECU. They agreed that a combined company would be stronger and better capitalized, and would have better access to capital markets as a result of increased size and the combination of current silver and other metals production in Mexico, the El Quevar advanced exploration project in Argentina, advanced exploration projects in Mexico and Peru, and a pipeline of advanced and reconnaissance exploration projects. They agreed that ECU's producing operations in Mexico would benefit from the operations expertise and experience of Golden's management, and that Golden's exploration efforts would benefit from the participation of ECU management. They also discussed the roles their respective management teams might have in the combined company, including the likelihood that Mr. Roy would serve as a consultant to the combined entity, and the potential for one of ECU's directors to serve on the board of directors of the combined company. They agreed that a business combination between the two companies was a mutually desirable prospect as an at-market merger of equals, although no specific exchange ratio was discussed at that time. They also discussed the possibility of Golden providing financing to ECU pending completion of an agreed business combination transaction. They agreed that Mr. Roy and members of his management would conduct a due diligence trip to Golden's El Quevar project during the week of May 23. They further agreed that it would be desirable for the two companies to enter into an exclusivity agreement, pursuant to which they would agree to continue discussions and negotiations regarding a business combination, and not to hold such discussions with other parties, until June 30, 2011.

        During the week of May 9, Golden engaged Davis Graham & Stubbs, LLP ("Davis Graham") and Fasken Martineau DuMoulin LLP ("Fasken Martineau") as its respective U.S. and Canadian legal advisors to assist in the potential transaction. During this week, Golden's legal and financial advisors began conducting their preliminary due diligence review of ECU's publicly available materials and preparing an exclusivity agreement and nonbinding proposal setting forth certain terms of a potential business combination.

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        On May 13, 2011, Mr. Clevenger provided the Golden board of directors with a written report regarding ECU and its business, together with the status of the due diligence investigation and discussions with ECU about a potential transaction.

        On May 19, 2011, the Golden board of directors held a regularly scheduled meeting in Golden, Colorado. At the meeting, Golden management presented the results of its technical due diligence investigation and Mr. Clevenger updated the board on the status of discussions with ECU regarding a potential strategic combination. At the same meeting, BMO Capital Markets presented to the Board its preliminary transaction perspectives, based on public information. The technical and legal due diligence process, regulatory filings and requirements, and an anticipated timeline were also discussed. After discussion, the Golden board of directors authorized members of Golden management to continue negotiations with ECU, including negotiation and execution of a nonbinding expression of interest and a binding exclusivity agreement.

        At Mr. Clevenger's invitation, a representative of The Sentient Group attended the May 19, 2011, Board meeting by telephone. Funds managed by affiliates of The Sentient Group own approximately 19.2 percent of Golden outstanding stock, and The Sentient Group and its representative have entered into a confidentiality agreement with Golden. At the Board meeting, the Sentient Group representative indicated its preliminary support for the potential transaction and asked to visit ECU's properties.

        On May 20, 2011, Mr. Clevenger delivered to Mr. Roy and Mr. Altmann drafts of a non-binding preliminary expression of interest, and a binding exclusivity agreement. During the week of May 23, 2011, the parties and their legal and financial advisors discussed the structure of a potential transaction and negotiated the terms of the non-binding expression of interest and exclusivity agreement.

        Also during the week of May 23, 2011, Mr. Roy and representatives of ECU's management conducted technical due diligence at Golden's El Quevar project in Argentina.

        On May 26, 2011, the Golden board of directors held a special meeting by telephone to consider the terms of the non-binding preliminary expression of interest and binding exclusivity agreement. At the meeting, Mr. Clevenger, Davis Graham and BMO Capital Markets briefed the board regarding the status of discussions with ECU and the proposed terms of the expression of interest and exclusivity agreement. After discussion, the board of directors unanimously authorized Golden management to continue negotiations with ECU, to present to ECU the negotiated non-binding preliminary expression of interest, to enter into the exclusivity agreement, to proceed with additional technical and legal due diligence and to present to ECU a draft business combination agreement.

        Following the board meeting, Mr. Clevenger and Mr. Altmann negotiated the final terms of the expression of interest and exclusivity agreement. On May 31, 2011, Golden submitted the non-binding preliminary expression of interest to ECU regarding a "merger of equals" transaction, which ECU countersigned. The expression of interest did not provide for an agreed-upon exchange ratio. The parties also entered into the exclusivity agreement pursuant to which the parties agreed not to pursue a business combination transaction with any other party until June 30, 2011.

        During the week of June 6, 2011, ECU and Golden each provided the other and their respective legal and financial advisors with access to an electronic data room containing non-public information responsive to the due diligence requests each had previously submitted to the other. Golden, ECU and their respective legal and financial advisors conducted due diligence reviews of materials provided until and including the date definitive transaction agreements were signed.

        In addition, Golden and its advisors continued to conduct additional on-site due diligence on ECU's properties. On June 2, 2011, Mr. Danni and a technical consultant expert in tailings dam construction, design and performance reviewed matters at ECU's properties related to the capacity of existing tailings facilities and the status of plans and permitting for a new tailings facility. Mr. Drips also visited ECU properties from May 31 to June 4, 2011. From June 7 through June 9, 2011,

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Mr. Danni and other representatives of Golden and a representative of Davis Graham conducted due diligence at the Velardeña Properties regarding various operational, community affairs, corporate and legal matters. During this visit the Golden representatives met with certain members of ECU senior management, including Mr. Roy. On June 15 and 16, 2011, Robert Vogels, Golden's Chief Financial Officer, met in Toronto with Dwight Walker, ECU's Chief Financial Officer, to discuss financial and accounting due diligence matters. On June 16 and 17, 2011, a metallurgical consultant hired by Golden conducted due diligence regarding metallurgical and recovery matters at ECU's properties. On June 1 and 2, 2011, a representative of The Sentient Group conducted due diligence at the ECU properties.

        On June 7, 2011, Mr. Altmann met with Mr. Clevenger at Golden's offices in Golden, Colorado and discussed certain management issues related to the combined company, additional deal terms and mechanics. Mr. W. Durand Eppler, a director of Golden, attended portions of that meeting.

        On June 10, 2011, members of ECU management conducted due diligence at Golden's Zacatecas properties in Mexico.

        On June 13, 2011, trading volume of ECU's common shares was approximately 3.4 million shares and the share price closed approximately 18% over the June 10, 2011 closing share price. The Toronto Stock Exchange contacted Mr. Altmann on June 13, 2011, regarding the increased trading activity and, in response to questions, Mr. Altmann and a representative of Blake Cassels & Graydon LLP, Canadian legal counsel to ECU, reported that ECU was conducting discussions with Golden regarding a potential business combination transaction, but that no definitive agreements had been entered into and no exchange ratio had been agreed.

        On June 13, 2011, Fasken Martineau sent a draft of the Arrangement Agreement to Blake, Cassels & Graydon LLP and Skadden, Arps, Slate, Meagher & Flom LLP, U.S. legal counsel to ECU. From then until June 24, 2011, the parties and their legal counsel negotiated the terms of the Arrangement Agreement and related documents, including a term sheet for a convertible debt financing contemplated to be provided by Golden to ECU, and exchanged drafts of the Arrangement Agreement and related documents. During this period, Mr. Clevenger also discussed with Mr. Altmann and with members of the compensation committee of Golden's board of directors the terms on which Mr. Altmann would serve as president of the combined company, if a strategic combination were completed.

        On June 22, 2011, Messrs. Roy and Clevenger met in Denver, Colorado and discussed certain issues related to strategic plans for the combined company.

        On June 22, 2011, the Golden board of directors held a special meeting by telephone which was also attended by Golden management and representatives of BMO Capital Markets, Davis Graham and Fasken Martineau. Davis Graham briefed the Board on the legal standards applicable in the context of evaluating a business combination of the type being considered. In the course of the meeting, members of Golden management and representatives of Davis Graham provided a final report on the due diligence investigation conducted and management's corresponding assessments. The diligence summary included a discussion of ECU's operations and plans, mineral qualities and processes, environmental matters, community relations, and other financial and legal matters. Representatives of Davis Graham and Fasken Martineau also provided an overview of the key terms of the proposed Arrangement Agreement, including termination rights and break-up fees under the Arrangement Agreement. The Golden board of directors then met in executive session to further discuss the information presented, including certain items that remained to be agreed by Golden including the exchange ratio, the amount of the break-up fee, the amount of expense reimbursement to be paid in the event of termination not resulting in a break-up fee and certain issues related to the interim financing. The board received the advice of its financial and legal advisors regarding these matters, authorized management to conclude the negotiation and scheduled a further meeting for the following day.

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        At Mr. Clevenger's invitation, a representative of The Sentient Group attended the June 22, 2011, Board meeting by telephone. At the Board meeting, the Sentient Group representative reiterated Sentient's support for the transaction and indicated that in the event the transaction was consummated, Sentient would be interested in investing further capital in the combined company to retain its current proportionate ownership.

        Over the evening of June 22 and through June 23, 2011, Mr. Clevenger and Mr. Altmann negotiated the final terms of the Arrangement Agreement, including the 0.05 exchange ratio, and Golden and ECU and their respective legal counsel and financial advisors worked to finalize the Arrangement Agreement, the terms of the related financing to be provided to ECU by Golden and related agreements. Following negotiations among the management and financial and legal representatives of Golden and ECU, the Golden board of directors held a special telephonic meeting on June 23, 2011, with members of Golden's management and legal and financial advisors. The Board received an update on resolution of the matters discussed the previous day and discussed the terms of the Arrangement Agreement and related financing. Representatives of BMO Capital Markets then presented to the board its final financial analysis of the proposed business combination and rendered to the Golden board an oral opinion (subsequently confirmed by delivery of a written opinion dated as of June 23, 2011) to the effect that, as of that date and based upon and subject to the factors, assumptions, qualifications and limitations to be set forth in such opinion, the 0.05 exchange ratio and cash consideration provided for in the Arrangement Agreement was fair, from a financial point of view, to Golden. Following discussion with its financial and legal advisors, the Golden board unanimously authorized execution of the Arrangement Agreement and related documents and recommended the issuance of Golden common stock pursuant to the Arrangement Agreement for approval by Golden's stockholders.

        With all remaining transaction issues having been settled during the night of June 23, 2011, the ECU board of directors on June 24, 2011 unanimously approved the proposed Transaction and the private placement.

        On June 24, 2011, members of Golden senior management and ECU senior management executed the Arrangement Agreement and a subscription agreement for the private placement described below, and issued a joint press release announcing the Transaction.

Subscription Agreement and Private Placement

        On July 13, 2011, ECU completed a private placement of Cdn$15.0 million, 0.0% senior unsecured convertible notes at par (the "Convertible Notes") to Golden pursuant to a subscription agreement (the "Subscription Agreement") between the parties dated June 24, 2011 (the "Private Placement"). Golden did not own or exercise control over any securities of ECU prior to the Private Placement. The Convertible Notes will mature on June 30, 2012 (subject to extension as described below), and are convertible by Golden at any time prior to 5:00 p.m. (Toronto time) on June 29, 2012, into common shares of ECU at the rate of 1,032 shares per $1,000 principal amount, consistent with the exchange ratio. As of July 13, 2011, the shares issuable upon conversion of the Convertible Notes represented approximately 4.7% of the outstanding common shares of ECU on an as-converted basis. The Convertible Notes are also redeemable at par by ECU at any time after the record date for voting upon the Transaction at the ECU securityholder meeting. In addition, ECU may elect to extend the maturity of the Convertible Notes for 6 months under certain conditions and upon a cash payment equal to 4% of the outstanding principal amount of the Convertible Notes, with interest accruing at 10% per annum during such extension period. The proceeds of the Private Placement were placed into escrow and are to be advanced to ECU pursuant to specific disbursement requests to be submitted to Golden and the escrow agent identifying the intended use of such funds. The Private Placement proceeds are to be used by ECU for general corporate purposes and to fund its ongoing expansion plans at the Velardeña Properties until closing of the Transaction.

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        Golden, as holder of the Convertible Notes, is entitled to vote any ECU common shares received upon conversion of the Convertible Notes before the record date for voting upon the Transaction at the ECU securityholder meeting or may vote the Notes themselves in any vote of ECU's outstanding common shares, options, warrants and convertible securities voting as a single class, including with respect to the votes of ECU Securityholders to approve the Transaction.

Golden's Reasons for the Transaction; Recommendation of Golden's Board of Directors

        On June 24, 2011, following completion of due diligence, Golden's board of directors, after an extensive review and thorough discussion of all facts and issues it considered relevant with respect to the proposed transactions, concluded unanimously that the Transaction and Private Placement are fair to, and in the best interests of, the Golden stockholders, and authorized Golden's executive officers to enter into the Arrangement Agreement, Subscription Agreement and related agreements and recommend to Golden stockholders that they vote in favor of the Share Issuance Proposal.

        In reaching its conclusion and making its recommendation, the members of Golden's board of directors consulted with Golden management, as well as its financial and legal advisors, and considered various other factors, both positive and negative. The following discussion of the information and factors considered by Golden's board of directors is not intended to be exhaustive and may not include all of the factors considered by the board. In view of the wide variety of factors considered by the Golden board in connection with its evaluation of the Transaction, the Golden board did not consider it practical to, nor did it attempt to, quantify, rank or otherwise assign relative weights to the specific factors that it considered in reaching its decision. In considering the factors described below, individual members of the Golden board may have given different weight to different factors. The Golden board considered this information as a whole and considered overall the information and factors to be favorable to, and in support of, its determinations and recommendations. The material information and factors considered by the Golden board included the following:

        Strategic Considerations.—Golden's board of directors considered a number of factors pertaining to the strategic rationale for the Transaction, including the following:

•

Portfolio Growth—The Transaction will provide Golden, through ECU's Velardeña project, with exposure to ECU's position in one of Mexico's most prolific silver belts, and access to a producing mine with significant potential growth prospects.



•

Value Creation—The Transaction is expected to allow Golden to leverage its existing excess cash position by supporting the further development and expansion of exploration and production at ECU's Velardeña Properties.



•

Unification of Complementary Management—Golden and ECU have complementary management teams with proven successful track records that are expected to allow the combined company to optimize existing development plans and mining operations. Upon completion of the Transaction, management will have a significant depth of experience in exploration, resource conversion, project development, and mining of both open pit and underground operations.



•

Geographic Diversification—The Transaction increases asset and geographic diversification benefits for Golden with production in Mexico and advanced exploration properties in Argentina, Mexico and Peru.



•

Increased Scale—The Transaction will create a combined company with greater scale, financial strength and an enhanced capital markets profile, with available funds to continue to advance expansion plans at Velardeña and the exploration of El Quevar. The Transaction will also provide Golden with exposure to new investors and is expected to improve the company's access to global capital markets to assist future growth objectives.

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•

Increased Portfolio of Silver Assets—The Transaction continues the strategy that Golden is currently pursuing of building a portfolio of quality silver producing assets in low political risk jurisdictions.

        Fairness Opinion—The fairness opinion provided by BMO Capital Markets on June 23, 2011, subsequently confirmed in writing, to the effect that, as of June 23, 2011, and based upon and subject to the analyses, factors, assumptions, qualifications and limitations set forth in such opinion, the exchange ratio and cash consideration was fair, from a financial point of view, to Golden.

        Recommendation of Management—The recommendation of Golden management in support of the Transaction.

        Stockholder Support—Sentient's expression of its support of the Transaction as one of Golden's largest stockholders, and Sentient's indication of its potential interest in investing additional capital in Golden following consummation of the Transaction in order to maintain its proportionate ownership interest in Golden.

        Due Diligence—The results of the due diligence review conducted by Golden's management and Golden's financial and legal advisors, including the information included in the disclosure letter delivered by ECU to Golden in connection with the Arrangement Agreement. The Golden board also considered the scope of the representations and warranties in the Arrangement Agreement in light of the matters raised in the course of the due diligence review.

        Ability to Accept a Superior Proposal—The fact that, under the terms of the Arrangement Agreement, the Golden board of directors remains able to respond in accordance with its fiduciary duties in the event of certain unsolicited proposals that are more favorable to Golden stockholders than the Transaction, and the fact that the ECU board has the same rights under the agreement.

        Golden Stockholder Approval—The fact that the issuance of Golden common stock to ECU shareholders pursuant to the Transaction must be approved by no less than a majority of the Golden common stock present at the special meeting and entitled to vote thereon. The Golden board of directors believes that the required stockholder approval protects the rights of Golden stockholders.

        Market and Industry Trends—Current economic, industry and market trends affecting Golden and ECU and the current and historical trading prices of their respective common stock.

        Consideration—The amount and type of consideration to be paid and issued pursuant to the Transaction and the fact that the Exchange Ratio is fixed to reflect an at-market combination at the time of negotiations and will not fluctuate based upon changes in the market price of Golden or ECU common stock between the date of the Arrangement Agreement and the date of the completion of the Transaction.

        Dilution of Golden Stockholders' Ownership Interest in the Combined Company—The fact that as a result of the issuance of Golden shares in the Transaction, Golden's existing stockholders will experience a significant degree of dilution in their ownership of Golden to approximately 49% of the combined company (or approximately 45% if all ECU options and warrants were exercised) while former shareholders of ECU will own approximately 51% of the combined company (or approximately 55% on a fully-diluted basis). Additionally, due to the fact that Golden's existing stockholders would hold less than 50% of the company following the Transaction, the board considered that the vesting of certain equity awards made to Golden's directors and officers would accelerate upon consummation of the Transaction, as it would be deemed a change of control of the company pursuant to the governing award agreements, and that certain severance payments may subsequently become payable to Golden executive officers upon the termination of their employment.

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        Restrictions on Business Operations—The fact that Golden and ECU would agree to restrictions on the conduct of each other's business during the period between the execution of the Arrangement Agreement and the completion of the Transaction.

        Termination Fee and Expense Reimbursement—The fact that Golden and ECU may be obligated to pay a termination fee or reimburse the other party's transaction expenses under the Arrangement Agreement in certain circumstances.

        No-Shop Provision—The fact that Golden and ECU would each agree to a "no-shop" clause pursuant to the Arrangement Agreement restricting each party's ability to solicit a competing transaction.

        Dissenters' Rights—The availability of dissenters' rights to the ECU shareholders in connection with the Transaction and the existence of a condition to closing which permits Golden to not close the Transaction if more than 5% of ECU shareholders exercise their dissenters' rights.

        The members of Golden's board of directors also considered potential risks associated with the Transaction, including among other things, the following:

        Inherent Uncertainty of Estimates—The fact that there was inherent uncertainty regarding the estimated value of the Velardeña Properties and the estimates of the future development costs that would need to be incurred with respect to the Velardeña Properties and about the quality, quantity and recoverability of any ore body at the Velardeña Properties.

        Business Risks—The risks associated with and inherent in ECU's business and its operations in Mexico, including the nature and potential scope of items identified pursuant to Golden's managements' and outside advisors' due diligence review and the inherent limitations of such processes.

        Market Disruption if Transaction Not Completed—The fact that if the Transaction is not completed, Golden may be adversely affected due to potential disruptions in its operations and market perceptions.

        Diversion of Management—The possible diversion of management's time and attention from the ongoing business of Golden due to the substantial time and effort necessary to complete the Transaction and plan for and implement the integration of the operations of Golden and ECU.

        Integration Challenges—The challenges inherent in the combination of two enterprises of the size and scope of Golden and ECU, and the risk that anticipated benefits, long-term as well as short-term, of the Transaction for Golden stockholders might not be realized.

        After consideration of these material factors, the Golden board concluded that the risks associated with the Transaction could be (i) mitigated or managed by Golden or, following the Transaction, by the combined company, (ii) were reasonably acceptable under the circumstances, and (iii) in light of the anticipated benefits overall, were significantly outweighed by the potential benefits of the Transaction. The Golden board realized that there can be no assurance about future results, including results considered or expected as described in the factors listed above, such as assumptions regarding the potential benefits of the Transaction. It should be noted that this explanation of the Golden board's reasoning and all other information presented in this section are forward-looking in nature and, therefore, should be read in light of the factors discussed under the heading "Cautionary Statements Regarding Forward-Looking Information" beginning on page [    •    ].

Fairness Opinion of Financial Advisor to Golden

        Golden retained BMO Capital Markets Corp. to render an opinion to the Golden board of directors as to the fairness, from a financial point of view, to Golden of the exchange ratio of 0.05 of a share of Golden common stock (which is referred to as the exchange ratio) and Cdn$0.000394 in cash,

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to be paid for each outstanding share of ECU stock in connection with the Transaction. On June 23, 2011, at a meeting of Golden's board of directors held to evaluate the Transaction, BMO Capital Markets delivered its oral opinion, which opinion was subsequently confirmed by delivery of its written opinion dated June 23, 2011, to the effect that, as of that date and subject to the various factors, assumptions, qualifications and limitations set forth in such opinion, the exchange ratio, together with the cash consideration payable in the Transaction, was fair, from a financial point of view, to Golden. BMO Capital Markets does not have any obligation to update, revise or reaffirm its opinion.

        The full text of BMO Capital Markets' written opinion to Golden board of directors, which sets forth, among other things, the procedures followed, assumptions made, matters considered and limitations on the review undertaken, is attached as Annex F to this proxy statement and is incorporated into this proxy statement by reference. Holders of Golden common stock are encouraged to read the opinion carefully and in its entirety. The following summary is qualified in its entirety by reference to the full text of such opinion. BMO Capital Markets' analyses and opinion were prepared for and addressed to the Golden board of directors and relate only to the fairness, from a financial point of view, to Golden of the exchange ratio and the cash consideration payable in the Transaction. BMO Capital Markets' opinion does not address any other aspect of the Transaction or the transactions contemplated by the Arrangement Agreement and such opinion does not constitute a recommendation to Golden Stockholders or anyone else on how to vote at any meeting held in connection with the Transaction. BMO Capital Markets' opinion also does not in any manner address the prices at which Golden or ECU common stock has traded or may trade in the future, including subsequent to the completion of the Transaction. The BMO Capital Markets opinion has been approved by a fairness committee of BMO Capital Markets.

        BMO Capital Markets provided the opinion described herein for the information and assistance of Golden's board of directors in connection with its consideration of the transactions contemplated by the Arrangement Agreement and Plan of Arrangement. The terms of the Arrangement Agreement and the Plan of Arrangement, and the Exchange Ratio and cash consideration payable, were determined through negotiations between Golden and ECU, and were approved by Golden's board of directors. BMO Capital Markets provided financial advice to Golden during such negotiations. However, BMO Capital Markets did not recommend any form of consideration to Golden or that any specific form of consideration constituted the only appropriate consideration for the Transaction.

        In preparing its opinion to the Golden board of directors, BMO Capital Markets performed various financial and comparative analyses, including those described below. The summary set forth below does not purport to be a complete description of the analyses underlying BMO Capital Markets' opinion or the presentation made by BMO Capital Markets to the Golden board of directors. The preparation of a fairness opinion is a complex analytic process involving various determinations as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances and, therefore, a fairness opinion is not readily susceptible to partial analysis or summary description. In arriving at its opinion, BMO Capital Markets did not attribute any particular weight to any analysis or factor considered by it, but rather made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses. Each of the analyses conducted by BMO Capital Markets was carried out in order to provide a different perspective on the financial terms of the Transaction and add to the total mix of information available. The analyses were prepared solely for the purpose of BMO Capital Markets providing its opinion and do not purport to be appraisals or necessarily reflect prices at which securities may be sold. BMO Capital Markets did not form a conclusion as to whether any individual analysis, considered in isolation, supported or failed to support an opinion about the fairness, from a financial point of view, to Golden of the exchange ratio and cash consideration payable. Rather, in reaching its conclusion, BMO Capital Markets considered the results of the analyses in light of each other and ultimately reached its opinion based on the results of the analyses taken as a whole. Accordingly,

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notwithstanding the separate analyses summarized below, BMO Capital Markets believes that its analyses must be considered as a whole and that selecting portions of its analyses and factors, or focusing on information presented in tabular format, without considering all of the analyses and factors or the narrative description of the analyses, would create a misleading or incomplete view of the process underlying its opinion.

        In arriving at its opinion, and performing the related financial analysis, BMO Capital Markets:

•

reviewed the June 23, 2011 draft of the Arrangement Agreement and Plan of Arrangement;



•

reviewed a draft copy of the Subscription Agreement between Golden and ECU;



•

reviewed internal management forecasts prepared by or on behalf of Golden and ECU;



•

reviewed operating and financial forecasts for Golden provided by the management of Golden and operating and financial forecasts for ECU provided by ECU's management and adjusted by management of Golden;



•

reviewed certain other internal information prepared by or on behalf of Golden;



•

reviewed public information (including that prepared by industry research analysts) relating to the business, operations, and financial condition and trading history of Golden, ECU, and other selected public issuers BMO Capital Markets considered relevant;



•

reviewed letters of representation as to certain factual matters and the completeness and accuracy of the information upon which the opinion is based provided by senior officers of Golden;



•

reviewed such other information, investigations, analyses and discussions as BMO Capital Markets considered necessary or appropriate in the circumstances;



•

conducted discussions with members of senior management and representatives of Golden concerning the respective operations, financial condition and prospects of Golden and ECU;



•

reviewed relevant financial contributions from both Golden and ECU to the combined entity resulting from the Transaction;



•

reviewed the pro forma impact of the Transaction on Golden, based on assumptions relating to transaction expenses, and purchase accounting assumptions determined by senior management of Golden;



•

reviewed historical stock prices of the common stock of Golden and ECU; and



•

reviewed such other financial studies and performed such other analyses and investigations and took into account such other matters as were deemed appropriate.

        In rendering its opinion, BMO Capital Markets assumed and relied on the accuracy and completeness of information supplied or otherwise made available to BMO Capital Markets by Golden, ECU or their representatives or advisors or obtained by BMO Capital Markets from other sources. BMO Capital Markets did not assume any responsibility for independently verifying and did not independently verify such information. BMO Capital Markets did not independently evaluate, physically inspect or appraise any of the respective assets or liabilities (contingent or otherwise) of Golden or ECU and was not furnished with any such valuations or appraisals. BMO Capital Markets was not asked to and did not evaluate the solvency or fair value of Golden or ECU. With respect to financial projections, including estimated synergies, for Golden and ECU, BMO Capital Markets was advised by Golden, and assumed, without independent investigation, that they had been reasonably prepared and reflected the best currently available estimates and good faith judgments of senior management of Golden and ECU (or, with respect to estimates and forecasts obtained from public sources, represent

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reasonable estimates and forecasts) of the expected future competitive, operating and regulatory environments and related financial performance of Golden and ECU. BMO Capital Markets was not asked to and did not consider the possible effects of any litigation or other legal claims. BMO Capital Markets further assumed that the Transaction will have the tax consequences described in discussions with, and materials furnished to BMO Capital Markets by, representatives of Golden. BMO Capital Markets also assumed that the Transaction will be consummated in a timely manner and in accordance with the terms of the Arrangement Agreement and Plan of Arrangement without waiver, modification or amendment of any material term, condition or agreement and that all governmental, regulatory and other consents and approvals necessary for the consummation of the Transaction will be obtained without any material adverse effect on Golden or ECU or on the contemplated benefits of the Transaction.

        BMO Capital Markets' opinion is necessarily based upon financial, economic, market and other conditions and circumstances as in effect on, and information made available to BMO Capital Markets as of June 23, 2011. BMO Capital Markets disclaims any undertakings or obligations to advise any person of any change in any fact or matter affecting the opinion which may come or be brought to its attention after the date of the opinion.

        BMO Capital Markets' opinion does not constitute a recommendation as to any action the board of directors of Golden should take in connection with the Transaction or any aspect thereof and is not a recommendation to any person on how such person should vote with respect to the adoption of the Arrangement Agreement or Plan of Arrangement or with respect to the Share Issuance Proposal. BMO Capital Markets' opinion relates solely to the fairness, from a financial point of view, to Golden of the exchange ratio and the cash consideration. BMO Capital Markets expresses no opinion as to the relative merits of the Transaction and any other transactions or business strategies discussed by the board of directors of Golden as alternatives to the Transaction or the decision of the board of directors of Golden to proceed with the Transaction, nor does BMO Capital Markets express any opinion on the structure, terms or effect of any other aspect of the Transaction or the other transactions contemplated by the Arrangement Agreement. BMO Capital Markets is not an expert in, and its opinion does not address, any of the legal, tax or accounting aspects of the proposed Transaction, including, without limitation, whether or not the transactions contemplated by the Arrangement Agreement constitute a change of control under any contract or agreement to which Golden, ECU or any of their respective subsidiaries is a party. BMO Capital Markets relied solely on Golden's legal, tax and accounting advisors for such matters.

        The following is a summary of the material analyses performed by BMO Capital Markets in connection with its opinion to the Golden board of directors dated June 23, 2011. The following summary, however, does not purport to be a complete description of the financial analyses performed by BMO Capital Markets, nor does the order of analyses described represent relative importance or weight given to those analyses by BMO Capital Markets. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before June 23, 2011 and is not necessarily indicative of current market conditions. Some of the financial analyses summarized below include information presented in tabular format. In order to understand fully BMO Capital Markets' financial analyses, the tables must be read together with the text of the summary. The tables alone do not constitute a complete description of the financial analyses. Considering the data set forth below without considering the full narrative description of the financial analyses, including the methodologies and assumptions underlying the analyses, could create a misleading or incomplete view of BMO Capital Markets' financial analyses.

        Arrangement Consideration.    BMO Capital Markets calculated the implied Transaction consideration price per share by multiplying the exchange ratio of 0.05 by the closing price per share of Golden's common stock on the Toronto Stock Exchange of Cdn$19.38 on June 23, 2011, plus the cash consideration of Cdn$0.000394 per share.

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        Stock Trading History.    To provide background information and perspective with respect to the historical share prices of Golden and ECU, BMO Capital Markets reviewed the share price performance and implied premium or discount to the implied Transaction consideration price per share, based on various time periods ending on June 23, 2011. The following table lists the implied premium or discount for these periods:

        Historical Exchange Ratio Analysis.    BMO Capital Markets analyzed and reviewed the historical trading price of Golden common stock relative to ECU common shares based on closing prices between June 24, 2008, and June 23, 2011, and calculated the historical exchange ratios during certain periods within those dates implied by dividing the daily closing prices per share of ECU's common shares by those of Golden's common stock, and the average of those historical trading ratios for the various periods reviewed. BMO Capital Markets next compared the exchange ratio of 0.05 provided for in the Transaction with historical exchange ratios for the various periods ending June 24, 2010, and June 23, 2011. The following table lists the implied exchange ratios for these periods:

        Relative Contribution Analysis.    BMO Capital Markets analyzed the contribution of each of Golden and ECU to the pro forma combined company with respect to net asset value (as defined below, the "NAV"), non-GAAP operating cash flow, ounces of production on a silver equivalent basis, measured and indicated resources and total resources on a silver equivalent basis, and current market capitalization. BMO Capital Markets analyzed the operating cash flow and production metrics for projected operating results for the fiscal year ending 2015 provided by Golden management. For the NAV, BMO Capital Markets utilized the projected operating results over the life-of-mine for both Golden and ECU's assets as provided by Golden management. Projected operating results were prepared by Golden and ECU management, respectively, and assumed no cost savings or other synergies.

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        The analyses yielded the following pro forma equity value contributions on a fully diluted in-the-money basis:

        NAV Overview.    To value Golden and ECU's key mining assets, El Quevar and the Velardeña Mining District respectively, BMO Capital Markets relied primarily on a discounted cash-flow ("DCF") analysis whereby it discounted the unlevered, after-tax, constant-dollar free cash flows of each asset over the life of the asset at different discount rates to generate present values. Based on a number of assumptions, each asset's real (or inflation-adjusted) discount rate was estimated and used to calculate the present value of the cash flows. All forecasts of free cash flow were based on Golden's management operating estimates, using consensus research analyst commodity price forecasts, and BMO Capital Markets' assessment thereof in the exercise of its professional judgment.

        Under the NAV approach, the value of El Quevar, the Velardeña Properties, and other mining assets are summed to produce a total asset value, from which is added or subtracted the company's financial assets and liabilities as well as an estimate of the present value of corporate general and administrative costs that were not directly assignable to the operating and development assets. The operating assumptions used in the DCF for both El Quevar and the Velardeña Properties are based on Golden's view of these two assets. These projections, as well as other estimates used by BMO Capital Markets in its analyses, were based on numerous variables and assumptions that are inherently uncertain, and accordingly, actual results could vary materially from those set forth in such projects.

        Accretion/Dilution Analysis.    BMO Capital Markets analyzed the expected pro forma impact of the Transaction on Golden's NAV per share on a fully diluted in-the-money basis, utilizing projections provided by Golden and ECU management teams which excluded any value ascribed to either anticipated expense synergies or further exploration upside. The analysis indicated that the Transaction would be accretive to Golden's stockholders on a NAV per share basis, excluding one-time Transaction costs associated with the transaction. Factoring in the estimated $13.0 million in transaction costs, the Transaction would be dilutive to Golden based on a NAV per share basis.

        Miscellaneous.    In performing its analyses, BMO Capital Markets made numerous assumptions with respect to industry performance, general business, economic, market and financial conditions and other matters, many of which are beyond the control of BMO Capital Markets, Golden or ECU. Any estimates contained in the analyses performed by BMO Capital Markets are not necessarily indicative of actual values or future results, which may be significantly more or less favorable than those suggested by such analyses. Additionally, estimates of the value of businesses or securities do not purport to be appraisals or to reflect the prices at which such businesses or securities might actually be sold. Accordingly, these analyses and estimates are inherently subject to substantial uncertainty. In addition, as described above, BMO Capital Markets' opinion was only one of several factors taken into consideration by Golden board of directors in making its determination to approve the Arrangement

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Agreement and the Plan of Arrangement. Consequently, BMO Capital Markets' analyses should not be viewed as determinative of the decision of Golden's board of directors or Golden's management with respect to the fairness of the consideration provided for in the Arrangement Agreement and the Plan of Arrangement.

        Golden retained BMO Capital Markets as its financial advisor based upon BMO Capital Markets' experience and expertise. BMO Capital Markets is a globally recognized investment banking and advisory firm. Pursuant to the terms of the engagement letter between Golden and BMO Capital Markets, Golden has agreed to pay BMO Capital Markets a transaction fee of approximately $3.5 million, $1.0 million of which was payable upon execution of the Arrangement Agreement and the rendering of its opinion, and approximately $2.5 million of which is contingent upon consummation of the Transaction. Golden also has agreed to reimburse BMO Capital Markets for reasonable expenses incurred by BMO Capital Markets in performing its services and to indemnify BMO Capital Markets and related persons and entities against liabilities, including liabilities under the U.S. federal securities laws, arising out of BMO Capital Markets' engagement.

        As part of its investment banking business, BMO Capital Markets is continually engaged in the valuation of businesses and their securities in connection with arrangements and acquisitions, negotiated underwritings, competitive biddings, secondary distributions of listed and unlisted securities, private placements and valuations for estate, corporate and other purposes. BMO Capital Markets has consulted with Golden from time to time on various matters, although none of such prior consultations involved a formal engagement of BMO Capital Markets by Golden. In addition, certain of BMO Capital Markets' affiliates are providing, and may have in the past provided, corporate banking services to Golden, or its affiliates from time to time, and BMO Capital Markets or its affiliates may provide investment and corporate banking services to Golden, ECU and their respective affiliates in the future for which BMO Capital Markets or they may have received or will receive customary fees. BMO Capital Markets provides a full range of financial advisory and securities services and, in the course of its normal trading activities, may from time to time effect transactions and hold securities, including derivative securities, of Golden or its affiliates for its own account and for the accounts of customers.

Voting Agreements

        On [    •    ], 2011, the officers and directors of both Golden and ECU entered into customary voting agreements, representing, in the aggregate, approximately [    •    ] million shares of Golden common stock (or [    •    ]%) and [    •    ] million ECU common shares (or [    •    ]%).

        Pursuant to these voting agreements, each Golden director and officer party to such agreement committed to vote in favor of approving the Transaction and, among other things, to:

•

not solicit, initiate, facilitate or encourage any inquiries or proposals, participate in any discussions (other than with ECU), approve or recommend, or accept or enter into, any agreement, understanding or arrangement, in respect of an Acquisition Proposal;



•

not sell, transfer, pledge, encumber or otherwise dispose of any Golden securities;



•

not grant any proxy or other right to vote any Golden securities (except to vote in favor of the Share Issuance Proposal and Charter Amendment Proposal) or enter into any voting trust or other agreement with respect to the right to vote Golden securities;



•

not take any action likely to prevent, hinder or delay or interfere with the completion of the Transaction;



•

not vote any Golden common stock in respect of any proposed action by Golden, the Golden Stockholders or any other person which would likely prevent, hinder or delay the completion of the Transaction;

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•

use all commercially reasonable efforts to assist ECU and Golden to complete the Transaction;



•

deliver, and not withdraw, a proxy in respect of all of his or her Golden common stock in support of the Transaction prior to the Golden stockholder meeting;



•

in the event that any transaction other than the Transaction is presented for approval of the Golden stockholders, not vote in favor of, accept, assist or otherwise further the completion of such transaction;



•

not purchase any securities of Golden's subsidiaries; and



•

take all steps as are necessary to ensure that its Golden securities will not be subject to any shareholders' agreements or voting trust or similar agreements affecting its Golden securities or the ability to exercise all voting rights attaching thereto.

Nothing contained in the voting agreements restricts, limits or prohibits a Golden director or officer from exercising his or her fiduciary duties to Golden in his or her capacity as a director or officer of Golden. The voting agreements between Golden and the ECU directors and management contained corresponding provisions relating to the voting of ECU shares by those directors and members of management.

Court Approval

        Under the Business Corporations Act (Québec), the Transaction requires court and ECU securityholder approval. On July 14, 2011, ECU obtained an interim order from the Québec Court providing for the calling and holding of the ECU special meeting and other procedural matters. Subject to receipt of the requisite approvals of the Transaction by ECU and Golden securityholders at their respective special meetings, the hearing in respect of a final order from the Québec Court is expected to take place on or about August 31, 2011.

Canadian Securities Law Matters

        ECU is a reporting issuer in all of the provinces of Canada. ECU common shares currently trade on the Toronto Stock Exchange ("TSX") under the symbol "ECU" and the ECU Warrants issued in February 2009 currently trade on the TSX under the symbol "ECU.WT." After the Transaction, ECU common shares and the ECU Warrants will be delisted from the TSX, and Golden will apply to the applicable Canadian securities regulators to have ECU cease to be a reporting issuer. Golden is a reporting issuer in the provinces of Alberta, British Columbia and Ontario. Golden common stock is listed on the TSX under the symbol "AUM" and on the NYSE Amex under the symbol "AUMN." It is a condition of the Transaction that the shares of Golden common stock issued to ECU shareholders pursuant to the Transaction, and which are reserved for issue upon exercise of the Golden Replacement Options and Golden Replacement Warrants, be conditionally approved for listing on the TSX and listed on the NYSE Amex, and that the Golden Replacement Warrants issued to holders of ECU's February 2009 Warrants pursuant to the Transaction be conditionally approved for listing on the TSX.

        The issuance of Golden common stock, Golden Replacement Options and Golden Replacement Warrants pursuant to the Transaction, and the issuance of Golden common stock upon the exercise of such Golden Replacement Options and Golden Replacement Warrants, will constitute distributions of securities which are exempt from the prospectus requirements of Canadian securities laws. Such Golden common stock, Golden Replacement Options and Golden Replacement Warrants may be resold in each province and territory of Canada, provided: (i) that Golden is a reporting issuer in a jurisdiction of Canada for the four months immediately preceding the trade; (ii) the trade is not a "control distribution" as defined National Instrument 45-102, Resale of Securities as adopted by the Canadian Securities Administrators; (iii) no unusual effort is made to prepare the market or create a demand for those securities; (iv) no extraordinary commission or consideration is paid in respect of that trade; and

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(v) if the selling security holder is an insider (as such terms are defined in the Canadian securities laws) or officer of Golden, the insider or officer has no reasonable grounds to believe that Golden is in default of Canadian securities laws.

Interests of, and Potential Payments to, Directors and Officers in Connection with the Transaction.

        In considering the recommendation of the Golden board of directors that Golden stockholders vote to approve the Share Issuance Proposal, you should be aware that our directors and executive officers have interests in the Transaction that may be different from, or in addition to, those of our stockholders generally. The board of directors of Golden was aware of and considered these potential interests, among other matters, in evaluating, negotiating and approving the Arrangement Agreement and the Plan of Arrangement, and in recommending the approval of the Share Issuance Proposal.

        Pursuant to Golden's 2009 Equity Incentive Plan (the "Incentive Plan"), any unvested awards made under the Incentive Plan (including stock options, restricted stock and restricted stock units) will vest immediately prior to the closing of any transaction in which stockholders of Golden immediately prior to the transaction own less than 50% of the outstanding voting power of the company following the transaction. At the time of the Transaction, each of Golden's executive officers will hold unvested stock options and/or restricted stock pursuant to the Incentive Plan. In addition, each of Golden's non-executive directors will hold unvested stock options pursuant to the Incentive Plan and unvested restricted stock units pursuant to Golden's Non-Employee Directors Deferred Compensation and Equity Award Plan, which was established under the Incentive Plan. Because the Transaction will result in ECU shareholders owning at least 51% of the voting power of the combined company, all such unvested stock options, restricted stock, and restricted stock units will vest immediately prior to the consummation of the Transaction in accordance with the terms of the Incentive Plan.

        In addition, we have entered into a change of control agreement with each of our executive officers. The change of control agreements contain "double trigger" severance provisions pursuant to which certain payments will be made to the executive if his or her employment is terminated by us or the surviving company, as applicable, without cause, or by the executive with good reason, within two years following a change of control. For purposes of these agreements, "cause" is defined to include a substantial and repeated failure to perform duties as reasonably directed by the board of directors, and "good reason" is defined to include certain adverse changes in the nature or status of the executive's duties or certain decreases in the compensation of the executive. Because the Transaction will result in ECU shareholders owning at least 51% of the voting securities of the combined company, the closing of the Transaction will constitute a change of control under the agreements. Payments made under the agreements are based on a multiple of the executive's salary and target bonus. Our Chief Executive Officer would be entitled to receive three times his salary and target bonus and each of the other executive officers would be entitled to receive two times his or her salary and target bonus. In order to ensure that our executives actually receive the intended benefits, the change of control agreements provide that we will reimburse the executive officers for the amount of the excise tax, if any, imposed on the change of control benefits under Internal Revenue Code Section 4999. This payment will be equal to an amount such that after the executive officer timely pays the excise tax, his or her liability for all taxes would be the same as if this tax had not applied. Receipt of benefits upon termination would be subject to the execution of a general release of claims by the executive officer or his or her beneficiary.

        We do not expect the employment of any of our executive officers to be terminated in connection with the Transaction, and therefore do not expect to make any severance payments under the change of control agreements unless a qualifying termination subsequently occurs within two years of the closing of the Transaction.

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Summary of Potential Payments to Golden's Directors and Officers

        Golden's directors will not receive any payments in connection with the Transaction. In connection with the Transaction, unvested restricted stock units held by our non-employee directors will vest. Directors will not be entitled to receive any shares vesting, but will be entitled to receive common stock upon retirement from the Board. Each non-employee director currently holds restricted stock units which will entitle such director to receive 2,871 shares of common stock. All of such awards will vest in connection with the Transaction.

        The following table indicates the estimated dollar amounts payable to Golden's named executive officers under the Incentive Plan and the change of control agreements described above upon the completion of the Transaction, assuming completion of the Transaction on [    •    ], 2011. Pursuant to SEC rules, amounts shown in the "cash," "perquisites/benefits" and "tax reimbursement" columns reflect an assumption that a qualifying termination of each executive's employment will occur contemporaneously with the closing of the Transaction. As described above, we do not expect the employment of any of our executive officers to terminate in connection with the Transaction, and therefore do not expect to make these payments unless a qualifying termination subsequently occurs within two years of the closing of the Transaction. Amounts shown in the "equity" column reflect the aggregate dollar value of previously awarded stock amounts and in-the-money option awards that will vest upon the closing of the Transaction, and are not new equity awards.

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Summary of Potential Payments to ECU Directors and Officers in Connection with the Transaction

        ECU has informed Golden that it has entered into a Change of Control Bonus Agreement with each of Michel Roy, the current Chairman and Chief Executive Officer of ECU, and Stephen Altmann, ECU's President. Under the terms of the Change of Control Bonus Agreements, upon consummation of the Transaction, Mr. Roy is entitled to receive Cdn$1.5 million and Mr. Altmann is entitled to receive Cdn$1.25 million. It is anticipated that Mr. Roy will agree to waive this payment and instead receive Cdn$1.5 million in shares of Golden common stock. In addition, as described below, in connection with the anticipated terms of Mr. Altmann's employment with Golden following the Transaction, it is anticipated that Mr. Altmann will waive the benefit of this payment and instead receive Cdn$1.25 million in Golden restricted stock, of which 40%, 40% and 20% would vest on the first, second and third anniversaries, respectively, of the grant date, or 100% upon termination of Mr. Altmann's employment with Golden.

        In addition to the Change of Control Bonus Agreements with Messrs. Roy and Altmann, the ECU board of directors has approved a discretionary pool of Cdn$500,000 to be paid, in the discretion of Messrs. Roy and Altmann, to certain officers or employees of ECU upon consummation of the Transaction. The recipients of the payments from this discretionary bonus pool have not been determined, but it is anticipated that Dwight Walker, ECU's Chief Financial Officer, would receive a payment of Cdn$150,000. Neither Mr. Roy nor Mr. Altmann are eligible to receive payments from this discretionary bonus pool. Amounts payable to Mr. Roy, Mr. Altmann and Mr. Walker in connection with the Transaction are shown in the table below:

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        In addition to the payments described above, the board of directors of ECU has approved the payment of certain amounts to Messrs. Roy and Altmann, as well as other members of ECU's management team, as compensation for past services. The payments are in lieu of option awards that ECU planned to award to the individuals; ECU had previously concluded that such option awards were not advisable because of ECU's ongoing review of strategic alternatives. The cash payments are equal to Cdn$175,000 for Mr. Roy, Cdn$150,000 for Mr. Altmann, and $100,000 in the aggregate for the remaining members of ECU's management team, as determined in the discretion of Messrs. Roy and Altmann. It is anticipated that ECU will make these payments prior to the consummation of the Transaction. These payments are not contingent upon the completion of the Transaction.

        Finally, the board of directors of ECU has approved the payment of certain amounts to each of the two independent directors of ECU as consideration for past services. The cash payments are equal to Cdn$12,000 (representing Cdn$3,000 per quarter for the last four calendar quarters), plus an additional cash payment of Cdn$50,000. This Cdn$50,000 payment is in lieu of option awards that ECU planned to award to the directors. It is anticipated that ECU will make these payments prior to the consummation of the Transaction. ECU advises that these payments are consistent with ECU's ordinary pay practices and are not contingent upon the completion of the Transaction.

Stephen Altmann Employment Arrangements

        In connection with the Transaction, Golden intends to offer Mr. Altmann the position of President, with an annual salary of $350,000, an annual target bonus equal to 50% of annual salary and an annual target equity award valued at 100% of annual salary. Mr. Altmann would waive benefits under his Change of Control Bonus Agreement with ECU and the Cdn$1.25 million bonus to be paid by ECU upon completion of the Transaction, and would instead receive Cdn$1.25 million in Golden restricted stock, of which 40%, 40% and 20% would vest on the first, second and third anniversaries, respectively, of the grant date, or 100% upon termination of Mr. Altmann's employment for any reason. Mr. Altmann would be offered a change of control agreement on the same terms as the change of control agreements with Golden's other executive officers, including an enhanced severance payment of 200% of target salary and bonus in the event of termination following a change of control, and would be eligible to participate in all other benefits available generally to all salaried employees of Golden.

        Mr. Altmann's responsibilities initially, in conjunction with Mr. Clevenger, would be the development and implementation of the growth plans of the combined company. Mr. Altmann would also have primary responsibility for investor relations.

Pro Forma Economic Ownership of Golden

        Upon completion of the Transaction, we estimate that former stockholders of ECU will own approximately 51% of the outstanding common stock of the combined company and that current Golden stockholders will own approximately 49%, assuming that no outstanding ECU options and warrants and any Replacement Options and Replacement Warrants are exercised before the consummation of the Transaction. Assuming that all such warrants and options are exercised before the consummation of the Transaction, former stockholders of ECU would own approximately 55% of the outstanding stock of the combined company on a fully diluted basis, while the current Golden stockholders would own approximately 45%.

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Dissenting Stockholder Rights

        Under applicable Delaware laws and U.S. securities laws, Golden stockholders are not entitled to dissenters' appraisal rights with respect to any matters to be acted upon at the Golden special meeting. Any registered holder of ECU common shares who properly dissents at the ECU special meeting in accordance with the Business Corporations Act (Québec) and the Plan of Arrangement will be entitled, in the event the Transaction becomes effective, to be paid by Golden, in accordance with the terms of the Plan of Arrangement, the fair value of the ECU common shares held by such dissenting ECU stockholder, determined by the Québec Court as of the close of business on the day before the ECU stockholder approval of the Transaction is obtained. If ECU shareholders holding greater than 5% of the outstanding ECU shares exercise dissenters' rights, Golden will not be obligated to consummate the Transaction.

Fees, Costs and Expenses

        Except as otherwise noted herein, all fees, costs and expenses incurred in connection with the Transaction will be paid by the party incurring those expenses.

Accounting Treatment

        Golden will account for the Transaction under U.S. GAAP as an acquisition of ECU by Golden. As required under U.S. GAAP, we considered all pertinent facts and circumstances in identifying Golden as the acquiring entity for accounting purposes. These facts and circumstances include the relative voting rights in the combined company of former holders of ECU common shares and holders of Golden common stock prior to the combination, the composition of the board of directors of the combined company and the terms of the exchange of Golden common stock for ECU common shares. The purchase price will be allocated to ECU's identifiable assets and liabilities based on their estimated fair market values at the date of the completion of the Transaction, and any excess of the purchase price over those fair market values will be allocated to mining properties. Final valuations of property, plant and equipment, mining properties and intangible and other assets have not yet been completed as management is still reviewing the existence, characteristics and useful lives of ECU's tangible and intangible assets. The completion of the valuation work could result in significantly different amortization expenses and balance sheet classifications. After completion of the Transaction, the results of operations of ECU will be included in the consolidated financial statements of Golden.

Material U.S. Federal Income Tax Consequences

        There are no material U.S. federal income tax consequences to Golden's current stockholders that will result from Golden's acquisition of ECU or the issuance of Golden common stock pursuant to the Transaction.

Supplemental Listings on NYSE Amex and TSX

        In connection with the Transaction, Golden has agreed to obtain conditional listing approval from the NYSE Amex and the TSX for the Golden common stock that will be issued in the Transaction, including the Golden common stock issuable upon exercise of the Golden Replacement Options and Golden Replacement Warrants. Golden has also agreed to obtain conditional approval for the listing and posting for trading on the TSX of the Golden Replacement Warrants issued to replace the February 2009 ECU Warrants.

Issuance and Resale of Golden Common Stock

        The Golden common stock to be issued pursuant to the Transaction has not been, and will not be, registered under the Securities Act or the securities laws of any other jurisdiction. The Golden common

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stock to be issued in the Transaction will be issued pursuant to an exemption from the prospectus requirements of Canadian securities law and from the registration requirements provided by Section 3(a)(10) of the Securities Act based on the approval of the Plan of Arrangement by the Québec Court.

        Section 3(a)(10) of the Securities Act exempts securities issued in exchange for one or more bona fide outstanding securities from the general requirement of registration where the fairness of the terms and conditions of the issuance and exchange of the securities have been approved by any court or authorized governmental entity, after a hearing upon the fairness of the terms and conditions of exchange at which all persons to whom the securities will be issued have the right to appear and to whom adequate notice of the hearing has been given. If the Québec Court approves the Plan of Arrangement, its approval will constitute the basis for the Golden Replacement Options and Golden Replacement Warrants to be issued without registration under the Securities Act in reliance on the exemption from the registration requirements of the Securities Act provided by Section 3(a)(10) of the Securities Act.

        On July 14, 2011, the Québec Court issued the interim order and, subject to the approval of the Plan of Arrangement by the ECU Securityholders and the approval of the Share Issuance Proposal by the Golden stockholders, a hearing for the Québec Court's final order on the fairness of the Transaction will be held on or about [    •    ] , 2011.

        Section 3(a)(10) of the Securities Act does not exempt the issuance of Golden common stock upon exercise of the Replacement Options or Replacement Warrants from the registration requirements of the Securities Act. Accordingly, pursuant to the terms of the Arrangement Agreement, Golden has agreed to file with the SEC a registration statement on Form S-8 and a registration statement on Form S-3 to register the Golden shares issuable upon the exercise of the Replacement Options and Replacement Warrants, respectively.

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ARRANGEMENT MECHANICS

Payment of Consideration

(a)

Following receipt of the Final Order and prior to the filing of the Articles of Arrangement with the Enterprise Registrar, Golden shall deposit with the Depositary in escrow, for the benefit of holders of ECU Securities, sufficient funds, shares of Golden common stock and Golden Replacement Warrants in the aggregate amounts necessary to pay the Consideration required by the Plan of Arrangement.

(b)

Subject to surrender to the Depositary for cancellation of a holder's ECU Share certificate or ECU Warrant certificate, together with the duly completed and executed Letter of Transmittal and such additional documents and instruments as the Depositary may reasonably require, following the Effective Time the holder of such surrendered certificate shall be entitled to receive the Consideration to which such holder is entitled under the Plan of Arrangement, less any amounts required to be deducted and withheld under applicable Laws in respect of taxes, and any certificate so surrendered shall forthwith be cancelled.

(c)

Until surrendered, each ECU Share certificate or ECU Warrant certificate shall be deemed after the Effective Time to represent only the right to receive, upon such surrender, the Consideration to which the holder thereof is entitled in lieu of such certificate under the Plan of Arrangement, less any amounts required to be deducted and withheld under applicable Laws in respect of taxes. Any such certificate formerly representing ECU Shares or ECU Warrants not duly surrendered on or before the sixth anniversary of the Effective Date shall cease to represent a claim by, or interest of, any former holder of ECU Shares or ECU Warrants of any kind or nature against or in ECU or Golden and be deemed to have been surrendered to Golden and shall be cancelled.

(d)

Any right or claim to payment pursuant to the Plan of Arrangement that remains outstanding on the sixth anniversary of the Effective Date shall cease to represent a right or claim of any kind or nature whatsoever and the right of the former ECU Securityholder to receive the Consideration pursuant to the Plan of Arrangement shall terminate and be deemed to be surrendered and forfeited, for no consideration, to Golden.

(e)

No holder of ECU Securities shall be entitled to receive any consideration with respect to its ECU Securities other than the Consideration in accordance with the Plan of Arrangement and, for greater certainty, no such holder will be entitled to receive any interest, dividends, premium or other payment in connection therewith.

Withholding Rights

        Golden, ECU and the Depositary, as applicable, shall be entitled to deduct and withhold from any Consideration payable or otherwise deliverable to any former holder of ECU Securities such amounts as they may be required to deduct and withhold therefrom under any provision of applicable Laws in respect of applicable taxes. Any such deducted and withheld amounts shall be treated as having been paid to the person to whom such amounts would otherwise have been paid.

No Fractional Securities will be issued

        No fractional shares of Golden common stock, fractional Golden Replacement Options or fractional Golden Replacement Warrants shall be issued to any person pursuant to the Plan of Arrangement. Instead, the number of shares of Golden common stock or the number of Golden Replacement Options or Golden Replacement Warrants to be issued to any person shall be rounded up or down, as applicable, to the nearest whole share of Golden common stock. In calculating such fractional interests, all ECU Shares, ECU Options or ECU Warrants, as applicable, registered in the name of or beneficially held by an ECU Securityholder or its nominee shall be aggregated.

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Distributions with Respect to Unsurrendered Certificates

        No dividend or other distribution declared or paid after the Effective Time with respect to Golden common stock shall be delivered to the holder of any certificate formerly representing ECU Shares unless and until the holder of such certificate shall have complied with the provisions of the Plan of Arrangement in respect of the surrender of such certificates. Subject to applicable law and to the Plan of Arrangement, at the time of such compliance, there shall, in addition to the delivery of the Consideration to which such holder is thereby entitled, be delivered to such holder, without interest, the amount of any dividend or other distribution declared or made after the Effective Time with respect to the Golden common stock to which such holder is entitled in respect of such holder's Consideration.

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THE ARRANGEMENT AGREEMENT

        The Transaction will be carried out pursuant to the Arrangement Agreement and the Plan of Arrangement. The following is a summary of the principal terms of the Arrangement Agreement. This summary does not purport to be complete and is qualified in its entirety by reference to the Arrangement Agreement, which has been filed by Golden on EDGAR at www.sec.gov and is appended hereto as Annex B.

        The Arrangement Agreement contains representations and warranties made by ECU and Golden. These representations and warranties were made by and to the parties thereto for the purposes of the Arrangement Agreement and are subject to the limitations and qualifications agreed to by the parties in connection with negotiating and entering into the Arrangement Agreement. In addition, these representations and warranties were made as of specified dates, may be subject to a contractual standard of materiality different from what may be viewed as material to Golden Stockholders or may have been used for the purpose of allocating risk between the parties rather than for the purpose of establishing facts. Moreover, information concerning the subject matter of the representations and warranties may have changed since the date of the Arrangement Agreement.

        On June 24, 2011, ECU and Golden entered into the Arrangement Agreement, pursuant to which ECU and Golden agreed that, subject to the terms and conditions set forth in the Arrangement Agreement, Golden will acquire all of the issued and outstanding ECU Shares, ECU Options and ECU Warrants. As a result of the Transaction, each ECU Shareholder (other than Dissenting Shareholders and Golden) will receive 0.05 of a share of Golden common stock and $0.000394 in cash for each ECU Share held. The terms of the Arrangement Agreement are the result of arm's length negotiation between ECU and Golden and their respective advisors.

Conditions Precedent to the Transaction

Mutual Conditions

        The obligations of the parties to complete the Transaction are subject to the satisfaction of each of the following conditions, each of which may only be waived with the mutual consent of ECU and Golden:

        (a)   the Arrangement Resolution shall have been approved and adopted by the ECU Shareholders and by the ECU Securityholders at the ECU Meeting in accordance with the Interim Order and applicable Law;

        (b)   the approval by Golden Stockholders of the Golden Meeting Resolution shall have been obtained at the Golden Meeting in accordance with applicable Law;

        (c)   the Interim Order and the Final Order shall each have been obtained on terms consistent with the Arrangement Agreement and satisfactory to the Parties, each acting reasonably, and shall not have been set aside or modified in a manner unacceptable to ECU and Golden, acting reasonably, on appeal or otherwise;

        (d)   there shall not exist any prohibition at Law, including a cease trade order, injunction or other prohibition or order at Law or under applicable legislation, against Golden or ECU which shall prevent the consummation of the Transaction;

        (e)   no action, suit or proceeding shall have been taken under any applicable Law or by any Governmental Entity, and no Law, policy, decision or directive (having the force of Law) shall have been enacted, promulgated, amended or applied, in each case (i) that makes consummation of the Transaction illegal, (ii) to enjoin or prohibit the Plan of Arrangement or the transactions contemplated by the Arrangement Agreement, (iii) which would render the Arrangement Agreement unenforceable in any way or frustrate the purpose and intent thereof, (iv) resulting in

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any judgment or assessment of damages, direct or indirect, which in the aggregate has had or could be reasonably expected to have an ECU Material Adverse Effect or a Golden Material Adverse Effect, (v) if the Transaction were consummated, could reasonably be expected to cause an ECU Material Adverse Effect or a Golden Material Adverse Effect, or (vi) seeks to prohibit or limit the ownership or operation by any Party or any of its affiliates of any material portion of its business or assets or to compel any Party or any of its affiliates to dispose of or hold separate any material portion of its business or assets as a result of the Transaction;

        (f)    the Golden common stock, Golden Replacement Options and Golden Replacement Warrants to be issued in the United States pursuant to the Plan of Arrangement shall be exempt from the registration requirements under the U.S. Securities Act of 1933 in reliance upon the Section 3(a)(10) Exemption or have been registered under the U.S. Securities Act;

        (g)   neither party shall have materially breached any of the terms or conditions of the Subscription Agreement and the Private Placement shall have been completed by no later than the date that is five (5) Business Days prior to the Record Date;

        (h)   the Key Regulatory Approvals shall have been obtained;

        (i)    the Key Third Party Consents shall have been obtained; and

        (j)    the Arrangement Agreement shall not have been terminated in accordance with its terms.

Additional Conditions in Favor of Golden

        The obligation of Golden to complete the Transaction is subject to the satisfaction of the following additional conditions (each of which is for the exclusive benefit of Golden and may be waived by Golden):

        (a)   all covenants of ECU under the Arrangement Agreement to be performed on or before the Effective Time shall have been duly performed by ECU in all material respects;

        (b)   all representations and warranties of ECU set forth in the Arrangement Agreement (other than those contained in Sections 3.1(c) (Organization and Qualification), 3.1(d) (Authority Relative to the Arrangement Agreement), 3.1(f) (Capitalization), 3.1(g) (Shareholder Rights Plan) and 3.1(w)(i) to 3.1(w)(iii) (Property)) of the Arrangement Agreement) shall be true and correct in all respects, without regard to any materiality or material adverse effect qualifications contained in them, as of the Effective Time, as though made on and as of the Effective Time (except for representations and warranties made as of a specified date, the accuracy of which shall be determined as of that specified date), except where the failure or failures of all such representations and warranties to be so true and correct in all respects would not reasonably be expected to have an ECU Material Adverse Effect, and the representations and warranties of ECU set forth in Sections 3.1(c) (Organization and Qualification), 3.1(d) (Authority Relative to the Arrangement Agreement),3.1(f) (Capitalization), 3.1(g) (Shareholder Rights Plan)) and 3.1(w)(i) to 3.1(w)(iii) (Property) of the Arrangement Agreement shall be true and correct in all respects as of the Effective Time, as though made on and as of the Effective Time;

        (c)   since the date of the Arrangement Agreement, there shall not have been any change, effect, event, occurrence, development or state of facts that in the aggregate has had or could reasonably be expected to have an ECU Material Adverse Effect;

        (d)   all loans made by ECU or any of its subsidiaries to an officer or director of ECU or any of its subsidiaries shall have been repaid in full;

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        (e)   Golden shall have received legal title opinions in respect of the Velardeña Property, the Chicago Property and the San Diego Property and legal corporate opinions in respect of each of ECU's subsidiaries;

        (f)    a flip-in event for the purposes of the Shareholder Rights Plan shall not have occurred;

        (g)   Michel Roy shall have transferred any shares held by him in Minera William S.A. de C.V., Minera Labri S.A. de C.V. and BLM Minera de Mexicana S.A. de C.V. as Golden may direct;

        (h)   holders of no more than 5% of the ECU Shares shall have exercised Dissent Rights;

        (i)    all loans made by officers and directors of ECU or its subsidiaries to ECU, or made by ECU or its subsidiaries to any officers and directors thereof, shall have been repaid without any penalty or premium; and

        (j)    all prospecting licences, exploration licences, mining leases, mining licences, mineral concessions and other forms of mineral tenure or other rights to Minerals, or to work upon lands for the purposes of exploring for, developing or extracting Minerals under any forms of mineral title (or any interest therein) recognized under applicable Laws, or other assets used or held for use in the business of ECU or its subsidiaries that as of the date of the Arrangement Agreement were held in the name of any person other than ECU or its subsidiaries shall have been transferred to ECU or one of its subsidiaries prior to the Effective Time.

Additional Conditions in Favor of ECU

        The obligation of ECU to complete the Transaction is subject to the satisfaction of the following additional conditions (each of which is for the exclusive benefit of ECU and may be waived by ECU):

        (a)   all covenants of Golden under the Arrangement Agreement to be performed on or before the Effective Time shall have been duly performed by Golden in all material respects, and ECU shall have received a certificate from Golden, addressed to ECU and dated the Effective Date, signed on behalf of Golden, by two of their senior executive officers (without personal liability), confirming the same as at the Effective Date;

        (b)   all representations and warranties of Golden set forth in the Arrangement Agreement (other than those contained in Sections 4.1(c) (Organization and Qualification), 4.1(d) (Authority Relative to the Arrangement Agreement), 4.1(f) (Capitalization) and 4.1(w)(i) to 4.1(w)(iii) (Property)) shall be true and correct in all respects, without regard to any materiality or material adverse effect qualifications contained in them, as of the Effective Time, as though made on and as of the Effective Time (except for representations and warranties made as of a specified date, the accuracy of which shall be determined as of that specified date), except where the failure or failures of all such representations and warranties to be so true and correct in all respects would not reasonably be expected to have a Golden Material Adverse Effect, and the representations and warranties of Golden set forth in Sections 4.1(c) (Organization and Qualification), 4.1(d) (Authority Relative to the Arrangement Agreement), 4.1(f) (Capitalization) and 4.1(w)(i) to 4.1(w)(iii) (Property) of the Arrangement Agreement shall be true and correct in all respects as of the Effective Time, as though made on and as of the Effective Time;

        (c)   Golden shall have delivered evidence satisfactory to ECU of the conditional approval of (i) the listing and posting for trading on the TSX and the NYSE Amex of the Golden common stock to be issued pursuant to the Plan of Arrangement and pursuant to the exercise of the Golden Replacement Options and Golden Replacement Warrants; and (ii) the listing and posting for trading on the TSX of the Golden Replacement Warrants issued to replace the ECU Warrants issued in February 2009;

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        (d)   ECU shall have received legal title opinions in respect of the El Quevar project and the Zacatecas Project and legal corporate opinions in respect of the Golden Material Subsidiaries;

        (e)   since the date of the Arrangement Agreement, there shall not have been any change, effect, event, occurrence, development or state of facts that in the aggregate, has had or could reasonably be expected to have a Golden Material Adverse Effect; and

        (f)    Golden shall have deposited or caused to be deposited with the Depositary, for the benefit of the ECU Securityholders, the aggregate Consideration to be paid for the ECU Securities under the Plan of Arrangement.

Covenants

Covenants

        ECU and Golden have each given, in favor of the other Party, usual and customary mutual covenants for an agreement of this nature including mutual covenants to conduct their respective businesses in the usual and ordinary course, to use their respective commercially reasonable efforts to satisfy or cause the satisfaction of the conditions precedent to their respective obligations under the Arrangement Agreement to the extent they are within such Party's control and to take, or cause to be taken, all other actions and to do, or cause to be done, all other things necessary, proper or advisable under applicable Laws to complete the Transaction.

Mutual Non-Solicitation Covenants

        Golden and ECU have each agreed that it will not, directly or indirectly, solicit, initiate, facilitate, or encourage the initiation of any inquiries or proposals, participate in any discussions or negotiations, or accept or enter into any agreement, understanding or arrangement regarding, or that may reasonably be expected to lead to, an Acquisition Proposal in respect of Golden or ECU, as applicable.

Adverse Recommendation Change

        ECU or Golden may each make an ECU Board Change in Recommendation or a Golden Board Change in Recommendation, as applicable, (i) following receipt of an Acquisition Proposal that it determines to be a Superior Proposal or (ii) solely in response to any Intervening Event, in each case if it determines in good faith, after consultation with its legal advisors, that the failure to take such action would be inconsistent with its fiduciary duties under applicable Law.

Superior Proposal; Right to Match or Respond to a Potential Adverse Recommendation Change

        Upon payment of the ECU Termination Fee, the ECU Board may terminate the Arrangement Agreement in order to accept and enter into an agreement in respect of an Acquisition Proposal that the ECU Board in good faith, after consultation with its financial and outside legal advisors, has determined is a Superior Proposal. Golden will have the right, but not the obligation, to amend the terms of the Transaction upon notification by ECU of a Superior Proposal or Intervening Event, as applicable, within a five (5) Business Day response period.

        Upon payment of the Golden Termination Fee, the Golden Board may terminate the Arrangement Agreement in order to accept and enter into an agreement in respect of an Acquisition Proposal that the Golden Board in good faith after consultation with its financial and outside legal advisors has determined is a Superior Proposal. ECU will have the right, but not the obligation, to amend the terms of the Transaction upon notification by Golden of a Superior Proposal or Intervening Event, as applicable, five (5) Business Day response period.

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Termination of the Arrangement Agreement

        The Arrangement Agreement may be terminated and the Transaction may be abandoned at any time prior to the Effective Time (notwithstanding any approval of the Arrangement Agreement or the Arrangement Resolution by ECU Shareholders or the ECU Securityholders or the Transaction by the Québec Court or the approval by the Golden Stockholders of the Golden Meeting Resolution):

        (a)   by mutual written agreement of ECU and Golden; or

        (b)   by either ECU or Golden, if:

          (i)  the Effective Time shall not have occurred on or before the Outside Date, except that such right to terminate the Arrangement Agreement shall not be available to any Party whose failure to fulfill any of its obligations or breach of any of its representations and warranties under the Arrangement Agreement has been the cause of, or resulted in, the failure of the Effective Time to occur by such Outside Date;

         (ii)  there are changes in the Law that makes consummation of the Transaction illegal or otherwise prohibited;

        (iii)  the Arrangement Resolution shall have failed to receive the requisite ECU Securityholders approval; or

        (iv)  the Golden Meeting Resolution shall have failed to receive the requisite Golden Stockholders approval;

        (c)   by Golden, if:

          (i)  the ECU Board makes an ECU Board Change in Recommendation;

         (ii)  subject to the terms of the Arrangement Agreement, Golden enters into a binding written agreement relating to a Superior Proposal; provided it pays the Golden Termination Fee;

        (iii)  any of the mutual conditions precedent or conditions precedent in favor of Golden in the Arrangement Agreement is not satisfied and is incapable of being satisfied by the Outside Date (provided Golden is not then in breach so as to cause any of such conditions not to be satisfied);

        (iv)  subject to ECU's right to remedy, a breach of any representation or warranty or failure to perform any covenant or agreement by ECU in the Arrangement Agreement shall have occurred that would cause the mutual conditions precedent or the conditions precedent in favor of Golden not to be satisfied, and such conditions are incapable of being satisfied by the Outside Date (provided Golden is not then in breach so as to cause any of such conditions not to be satisfied);

         (v)  ECU is in material breach or in default of any of either its non-solicitation or right to match obligations or covenants in the Arrangement Agreement or the Exclusivity Agreement; or

        (vi)  the ECU Meeting has not occurred within 95 days from the date of the Arrangement Agreement; (unless Golden's failure to fulfil any obligation is the direct cause of, or directly results in, the failure of the ECU Meeting to occur on or before such date).

        (d)   by ECU, if

          (i)  the Golden Board makes a Golden Board Change in Recommendation;

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         (ii)  subject to the terms of the Arrangement Agreement, ECU to enters into a binding written agreement relating to a Superior Proposal; provided it pays the ECU Termination Fee;

        (iii)  any of the mutual conditions precedent or conditions precedent in favor of ECU in the Arrangement Agreement is not satisfied and is incapable of being satisfied by the Outside Date (provided ECU is not then in breach so as to cause any of such conditions not to be satisfied);

        (iv)  subject to Golden's right to remedy, a breach of any representation or warranty or failure to perform any covenant or agreement by Golden in the Arrangement Agreement shall have occurred that would cause the mutual conditions precedent or the conditions precedent in favor of ECU not to be satisfied, and such conditions are incapable of being satisfied by the Outside Date (provided ECU is not then in breach so as to cause any of such conditions not to be satisfied);

         (v)  Golden is in material breach or in default of a non-solicitation or right to match obligations or covenants set forth in the Arrangement Agreement or the Exclusivity Agreement; or

        (vi)  the Golden Meeting has not occurred within 95 days from the date of the Arrangement Agreement (unless ECU's failure to fulfil any obligation is the direct cause of, or directly results in, the failure of the Golden Meeting to occur on or before such date).

Termination Fee

ECU Termination Fee

        ECU will pay the ECU Termination Fee in the amount of Cdn$10,000,000 to Golden if an ECU Termination Fee Event occurs, meaning the termination of the Arrangement Agreement:

        (a)   by Golden following an ECU Board Change in Recommendation or if ECU is material breach or in default of any of its obligations or covenants under the Arrangement Agreement with respect to non-solicitation, the right to match or the Exclusivity Agreement;

        (b)   by ECU following the authorization by the ECU Board to enter into a binding written agreement relating to a Superior Proposal in accordance with the terms of the Arrangement Agreement; or

        (c)   by either Golden or ECU if the Effective Date shall not have occurred by the Outside Date or if the Arrangement Resolution shall have failed to receive the requisite ECU Shareholder approval, or by Golden due to a breach of any representation or warranty or failure to perform a covenant by ECU that would cause the mutual conditions precedent and conditions precedent in favor of Golden not to be satisfied or if the ECU Meeting has not occurred within 95 days of the date of the Arrangement Agreement, but only if:

          (i)  in the case of termination of the Arrangement Agreement by reason of the Effective Date not having occurred by the Outside Date or pursuant to a breach of any representation or warranty or failure to perform a covenant by ECU that would cause the mutual conditions precedent and conditions precedent in favor of Golden not to be satisfied, prior to such termination an Acquisition Proposal in respect of ECU shall have been made or publicly announced by any person; or

         (ii)  in the case of termination of the Arrangement Agreement by reason of the ECU Meeting not having occurred within 95 days of the date of the Arrangement Agreement or if the Arrangement Resolution shall have failed to receive the requisite ECU Securityholder

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approval, prior to the ECU Meeting, an Acquisition Proposal in respect of ECU shall have been publicly announced by any person;

        (iii)  and, in either case:

        (A)  within 12 months following the date of such termination an Acquisition Proposal relating to ECU is consummated; or

        (B)  within 6 months following the date of such termination ECU and/or one or more of its subsidiaries enters into a definitive agreement in respect of, or the ECU Board approves or recommends, a transaction contemplated by (i) above and that transaction is subsequently consummated at any time thereafter.

Golden Termination Fee

        Golden will pay the Golden Termination Fee in the amount of Cdn$10,000,000 to ECU if a Golden Termination Fee Event occurs, meaning the termination of the Arrangement Agreement:

        (a)   by ECU following a Golden Board Change in Recommendation or if Golden is material breach or in default of any of its obligations or covenants under the Arrangement Agreement with respect to non-solicitation, the right to match or the Exclusivity Agreement;

        (b)   by Golden following the authorization by the Golden Board to enter into a binding written agreement relating to a Superior Proposal in accordance with the terms of the Arrangement Agreement; or

        (c)   by either Golden or ECU if the Effective Date shall not have occurred by the Outside Date or if the Golden Meeting Resolution shall have failed to receive the requisite Golden stockholder approval, or by ECU pursuant due to a breach of any representation or warranty or failure to perform a covenant by Golden that would cause the mutual conditions precedent and conditions precedent in favor of ECU not to be satisfied or if the Golden Meeting has not occurred within 95 days from the date of the Arrangement Agreement, but only if:

          (i)  in the case of termination of the Arrangement Agreement by reason of the Effective Date not having occurred by the Outside Date or pursuant to a breach of any representation or warranty or failure to perform a covenant by Golden that would cause the mutual conditions precedent and conditions precedent in favor of ECU not to be satisfied, prior such termination an Acquisition Proposal in respect of Golden shall have been made or publicly announced by any person; or

         (ii)  in the case of termination of the Arrangement Agreement by reason of the Golden Meeting note having occurred within 95 days of the date of the Arrangement Agreement or if the Golden Meeting Resolution shall have failed to receive the requisite Golden stockholder approval, prior to the Golden Meeting, an Acquisition Proposal in respect of Golden shall have been publicly announced by any person;

        (iii)  and, in either case:

        (A)  within 12 months following the date of such termination an Acquisition Proposal relating to Golden is consummated; or

        (B)  within 6 months following the date of such termination Golden and/or one or more of its subsidiaries enters into a definitive agreement in respect of, or the Golden Board approves or recommends, a transaction contemplated by (i) above and that transaction is subsequently consummated at any time thereafter.

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Expense Reimbursement

        In the event the Arrangement Agreement is terminated:

        (a)   by Golden as a result of a breach of any representation or warranty or failure to perform a covenant by ECU that would cause the mutual conditions precedent and conditions precedent in favor of ECU not to be satisfied or if the ECU Meeting has not occurred within 95 days from the date of the Arrangement Agreement, ECU shall pay to Golden Cdn$2,500,000 as an expense reimbursement; and

        (b)   by ECU as a result of a breach of any representation or warranty or failure to perform a covenant by Golden that would cause the mutual conditions precedent and conditions precedent in favor of ECU not to be satisfied or if the Golden Meeting has not occurred within 95 days from the date of the Arrangement Agreement, Golden shall pay to ECU Cdn$2,500,000 as an expense reimbursement.

Amendment of the Plan of Arrangement

        The Plan of Arrangement may be amended, modified and/or supplemented as follows:

        (a)   ECU and Golden may amend, modify or supplement the Plan of Arrangement at any time prior to the Effective Time, provided that any amendment, modification or supplement must be contained in a written document which is agreed to in writing by ECU and Golden and filed with the Court and, if made following the ECU Meeting, approved by the Court and communicated to ECU Securityholders in the manner required by the Court (if so required);

        (b)   any amendment, modification or supplement to the Plan of Arrangement may be proposed by ECU at any time prior to or at the ECU Meeting, provided that Golden has consented to such amendment, modification or supplement, with or without any other prior notice or communication and, if so proposed and accepted by the persons voting at the ECU Meeting, shall become part of the Plan of Arrangement for all purposes; and

        (c)   any amendment, modification or supplement to the Plan of Arrangement which is approved or directed by the Court following the ECU Meeting shall be effective only if it is consented to in writing by ECU and Golden and, if required by the Court, is consented to by the ECU Securityholders.

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THE COMBINED COMPANY UPON COMPLETION OF THE TRANSACTION

        Upon completion of the Transaction, ECU will become a wholly-owned subsidiary of Golden. The business and operations of Golden and ECU will be consolidated and the principal executive office of the combined company will be at Golden's current office in Golden, Colorado at 350 Indiana Street, Suite 800, Golden, Colorado, 80401, and the registered office will be the Corporation Trust Company, 1209 Orange Street, Wilmington, Delaware, 19801.

Business of the Combined Company

ECU's Velardeña Properties, Durango, Mexico

        Following completion of the Transaction, Golden plans to continue to operate the mines on the Velardeña Properties and to advance the expansion of these operations as currently being considered by ECU. In 2010, the mines on the Velardeña Properties produced approximately 380,000 ounces of silver, 10,000 ounces of gold, 182,000 pounds of zinc, and 155,000 pounds of lead. In the first quarter of 2011, the mines on the Velardeña Properties produced approximately 79,000 ounces of silver, 1,900 ounces of gold, 43,000 pounds of zinc, and 47,000 pounds of lead. Golden has developed a plan to test potential improvements to the grinding and process controls and optimization of certain circuit retention times that could result in low cost productivity improvements in the existing oxide plant. Golden is developing a plan for grade control in the mines that could improve the grade of ore processed through the oxide plant.

        Golden has developed a metallurgical testing plan focused on improving metal recoveries and product (concentrate) qualities for the planned sulfide plant. Golden intends to conduct various test work to determine optimal metallurgical characteristics of both the oxide and sulfide ores. For the planned sulfide plant, crushing, grinding and flotation parameters would be examined to produce a process flow sheet which optimizes value from the silver, gold, lead and zinc minerals contained in the deposit. Following completion of this work, Golden expects to produce a NI 43-101 compliant Preliminary Economic Assessment. Current target production rates for the anticipated new sulfide plant are approximately 2000 tonnes per day. Golden's current preliminary estimate of the cost to complete a 2000 tonne per day sulfide plant and associated 7500 meters of underground mine development is approximately $120 million, with testwork, engineering and construction and mine development being completed over about a three year period. The new sulfide plant is currently expected to produce annually approximately 4 million silver ounces, 70,000 gold ounces and 15 to 20 million pounds each of lead and zinc. Golden currently expects that the existing oxide plant would continue to operate while the new sulfide plant is built and may continue to operate following commencement of production from the new sulfide plant.

Golden's El Quevar Project, Salta, Argentina

        Golden has been focused on advancing its El Quevar silver project and has completed more than 820 meters of development drifting. The drifting has encountered a large number of mineralized structures believed to be tension faults that were not anticipated in the current model of the El Quevar deposit, in which mineral concentrations are modeled to follow the alteration envelope. As a result, we decided to delay completion of a NI 43-101 compliant Preliminary Economic Assessment and a planned mid-year 2011 resource update to allow further work to assess the impact that these newly discovered structures may have on the mining plan and global El Quevar resource.

        As part of this effort, Golden is currently examining the bulk mining potential of the Yaxtché zone at El Quevar. Preliminary engineering indicates that an open pit could be feasible on the eastern end of the Yaxtché zone and Golden is performing an optimization analysis of the potential pit. Following completion of these analyses, Golden plans to examine the potential for bulk underground mining of the higher grade western zone. We may reduce our level of activity in advancing the drift until this

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work has been completed, as the open pit would encompass the area through which the drift would advance. Golden has targeted the fourth quarter 2011 for a resource update based on the bulk mining studies. If these efforts are successful, Golden plans to proceed with a NI 43-101 compliant Preliminary Economic Assessment in the first half of 2012.

Golden's Pánuco Exploration Target, Zacatecas, Mexico

        Golden has commenced a third drilling program at its Pánuco exploration target at the Zacatecas properties in the state of Zacatecas, Mexico. Results from the first two rounds of drilling have identified a vein system striking one and a half kilometers with silver grades up to one kilogram per tonne over more than a meter. More than 70 percent of the approximately 48 holes drilled in the first two drilling programs encountered silver mineralization averaging about 270 grams of silver per tonne. The third drilling program is planned to include an additional 40 to 50 holes for a total of approximately 100 holes. Golden expects that the results of the three drilling programs will support preparation of a NI 43-101 compliant estimate in the first half of 2012.

Other Golden Exploration Properties

        Golden is also advancing other exploration properties, and is currently focused on the three prospects described below.

        At the Cochabamba silver prospect in the Ancash Province of Peru, Golden is preparing for a 10 hole program to test an outcropping vein system of more than 1.5 kilometers in length characterized by quartz and carbonate vein material containing gold, silver and base metals. Surface and limited underground sampling has returned up to 10 grams per tonne gold, 450 grams per tonne silver and more than 3% combined lead and zinc. A similar occurrence ten kilometers to the northeast is characterized by a high grade resource averaging 17 grams per tonne gold and 450 grams per tonne silver.

        At the Atlas gold prospect in the Santa Cruz Province of Argentina, Golden is conducting field geologic work to prepare for a 10 to 20 drill hole program prior to year-end 2011. Golden has identified a system at Atlas characterized by epithermal veins in a zone about 1.5 kilometers in length and 40 meters width where surface channel sampling has returned gold values ranging from 0.5 grams to 10 grams per tonne gold.

        At the La Pinta prospect, directly south of Goldcorp's Penasquito mine in Zacatecas state, Mexico, Golden is conducting a geophysical survey in an attempt to define the source of intrusive float anomalous in zinc and silver and up to three grams per tonne gold found on the top of a ridge in the center of the property. Depending on the results of this survey, Golden may drill the prospect in the later part of the year.

Directors and Officers of the Combined Company

        The current directors and officers of Golden will continue to serve as the directors and officers of Golden after the completion of the Transaction, with the following changes:

•

Michael T. Mason, a current director of ECU, will join the board of directors of Golden, bringing the total number of directors to seven. Mr. Mason has more than 35 years experience in the minerals industry. Over the course of his career he has held several senior positions, and has been engaged in providing evaluation, marketing, development and/or financing strategies for various projects. Currently he is both a director and President of MBMI Resources Inc., a nickel development company. He is also a managing partner of Mineral Services, LLC, chief operating officer of Global Gold Corporation and a director of Euromax Resources Ltd and Geovic Ltd.

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•

Stephen Altmann, the current president of ECU, will assume the position of president of Golden. Mr. Altmann joined ECU in January 2007. He previously worked as an investment banker, providing financial and strategic advice to a large number of domestic and international public companies. From 2000 to 2006, Mr. Altmann was a director in the mergers and acquisitions group at Scotia Capital, providing strategic advice to mining and industrial product clients and later became a managing director for the mining group at Desjardins Securities. From 1994 to 2000, Mr. Altmann worked in the corporate finance department of RBC Dominion Securities and later, was a vice president at Credit Suisse First Boston, where he was primarily responsible for coverage of companies in the mining sector. Mr. Altmann worked as a geophysicist prior to his investment banking career. Mr. Altmann holds a Masters of Business Administration from McMaster University and an Honours Bachelor of Science (Geophysics) degree from the University of Western Ontario.

For additional information regarding Mr. Altmann's anticipated service as president of Golden following the Transaction, see "Summary of Potential Payments to ECU Directors and Officers in Connection with the Transaction."

•

Michel Roy, the current chairman and chief executive officer of ECU, will act as a senior consultant to Golden.

Capital Structure

        If the Charter Amendment Proposal is not approved by our stockholders at the special meeting, or if the Charter Amendment Proposal is approved but the Share Issuance Proposal is not approved, the authorized capital of Golden will continue to consist of 50,000,000 shares of common stock, $0.01 par value, and 10,000,000 shares of preferred stock, $0.01 par value. If the Charter Amendment Proposal is approved by our stockholders at the special meeting and the Transaction is consummated, the authorized capital of Golden will consist of 100,000,000 shares of common stock, $0.01 par value, and 10,000,000 shares of preferred stock, $0.01 par value. In either event, the rights and restrictions of the classes of capital stock of Golden will not be affected by the Transaction.

        In connection with the Transaction, ECU shareholders will receive 0.05 shares of Golden common stock and Cdn$0.000394 in cash for each ECU common share held immediately prior to the consummation of the Transaction. As of June 24, 2011, the date of the Arrangement Agreement, ECU had 317,081,333 shares outstanding and an additional 3,000,000 shares are expected to be issued by ECU prior to the closing as payment for the prior exercise of an option to purchase an exploration property. Assuming that no ECU options or warrants are exercised after June 24, 2011, ECU would have 320,081,333 shares outstanding, and Golden would issue approximately 16,004,066 shares to ECU shareholders at closing. The exact number of shares issued at closing will be subject to adjustment for rounding. In addition, as further discussed below, assuming that none of the ECU options or warrants are exercised prior to the closing date, 661,750 Golden shares would be issuable upon exercise of

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Golden Replacement Options and 2,218,292 Golden shares would be issuable upon exercise of Golden Replacement Warrants. A summary post-Transaction equity capitalization table is set forth below:

Golden Minerals
Summary Equity Capitalization Table(1)

Golden Replacement Options

        As of June 24, 2011, ECU had a total of 13,235,000 outstanding options to purchase common shares. All ECU options are vested and currently exercisable.

        Effective at the closing of the Transaction, Golden plans to adopt a stock option plan containing substantially the same terms as the existing ECU Stock Option Plan, and the Golden Replacement Options will be issued pursuant to this plan. Other than the Golden Replacement Options, no awards will be made pursuant to this plan.

        The ECU options were issued to employees, directors or consultants of ECU. Upon termination of employment or other service to the company, the ECU options are exercisable until the earlier of (i) the original expiration date for the options, (ii) 90 days following the termination of employment or service (or, for persons engaged in certain investor relations activities, 30 days following termination of employment or service), or (iii) in the event of the optionholder's death, 12 months following the date of death. The expiration date of the Golden Replacement Options will be identical to the expiration date of the ECU options for which they are exchanged, provided, however, that the Golden Replacement Option Plan will provide that if any optionholder ceases to be an employee, officer, director or consultant of ECU within 180 days following the closing date, the expiration date for the Golden Replacement Options held by such person will be the earlier of (i) the original expiration date for the options, or (ii) two years following the closing date.

        If none of the ECU options are exercised prior to the closing date, the Golden Replacement Options issued to the optionholders would be issuable for an aggregate of approximately 661,750 shares of Golden common stock. The exact number of shares issuable upon exercise of the Golden

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Replacement Options would be subject to adjustment for rounding. The number of shares and expiration date of the Golden Replacement Options are set forth in the table below:

Golden Replacement Warrants

        As of June 24, 2011, ECU had outstanding warrants exercisable for a total of 44,365,826 common shares, including 36,638,576 ECU Warrants issued in February 2009 and 7,727,250 ECU Warrants issued in December 2009. Assuming that none of the ECU Warrants are exercised prior to the closing date, the Golden Replacement Warrants issued to the ECU warrantholders would be issuable for an aggregate of approximately 2,218,292 shares of Golden common stock. The exact number of shares issuable upon exercise of the Golden Replacement Warrants would be subject to adjustment for rounding. The number of warrant shares, expiration date and exercise price for the Golden Replacement Warrants are set forth in the table below:

        The February 2009 ECU Warrants currently trade on the TSX under the symbol "ECU.WT." After the Arrangement, the February 2009 ECU Warrants will be delisted from the TSX and as a condition of the Arrangement, Golden will apply for listing on the TSX of the Golden Replacement Warrants issued to replace the February 2009 ECU Warrants.

Unaudited Pro Forma Condensed Combined Financial Statements

        The Golden unaudited pro forma combined condensed financial information as of March 31, 2011, for the three-month period then ended and for the fiscal year ended December 31, 2010, is attached as Annex E to this proxy statement. The pro forma financial information is presented to show the results of operations and financial position of Golden as if the Transaction had occurred as of January 1, 2010, and with respect to the balance sheet, as if the Transaction had occurred as of March 31, 2011.

Liquidity and Capital Resources of the Combined Company

        At March 31, 2011 our aggregate cash and short-term investments totaled $106.1 million, which included $104.3 million of cash and cash equivalents and $1.8 million of short-term investments. Our cash and short-term investment balance is lower than the $121.6 million in similar assets held at December 31, 2010 due to approximately $16.9 million spent during the three months ended March 31, 2011 on the El Quevar project, exploration and general and administrative activities, including changes

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in working capital, offset partially by the receipt of approximately $1.4 million of common shares in Apogee Silver Ltd. ("Apogee") in connection with our sale to Apogee of the Golden subsidiary holding the Paca Pulacayo property.

        As of July 13, 2011, Golden held Cdn$15.0 million of ECU 0.0% senior unsecured convertible notes, which it received in exchange for Cdn$15.0 million of cash invested in ECU through a private placement. The proceeds of the convertible notes are intended to be used by ECU for general corporate purposes and for ongoing exploration, development, and operations at Velardeña until closing of the proposed Transaction, to the extent that current ECU cash flows from the sale of doré and concentrates are not sufficient to fund those expenditures. Among the ECU expenditures which may be funded from the proceeds of the convertible notes are expenditures related to the Transaction and for scheduled debt service. Golden anticipates that ECU's current cash flow from sales will be sufficient to fund ongoing operations at Velardeña until closing of the Transaction. However, Golden anticipates that prior to closing ECU will spend approximately Cdn$12.5 million of the proceeds from the convertible notes for costs related to exploration and capital equipment at Velardeña, ECU corporate overhead, debt service, and costs related to the Transaction, including bankers and attorneys fees. Following the closing of the Transaction, the remaining Cdn $2.5 million of proceeds from the convertible notes would, unless used for other purposes, be available for Golden's general use.

        With our cash and investment balance at March 31, 2011 of $106.1 million, and assuming that we are able to close the Transaction prior to the end of September 2011, we plan to spend the following amounts during the remaining nine months of 2011 pursuant to our long-term business strategy:

•

Approximately $12.5 million for corporate overhead, debt service and costs related to the Transaction incurred by ECU, reflected as a drawdown of proceeds from the $15.0 million ECU convertible note held by Golden;



•

Approximately $5.0 million of costs related to the Transaction incurred by Golden;



•

Approximately $22.0 to $25.0 million to be incurred at our El Quevar project to fund the continuation of exploration drilling, underground drifting, and related technical engineering and project assessment to further define the extent of the resource before completing an economic study. This amount could be reduced if we conclude that the advancement of the underground drift is no longer necessary as referenced in "—Business of the Combined Company—Golden's El Quevar Project, Salta, Argentina.";



•

Approximately $4.0 million of costs related to the advancement of feasibility work at ECU's Velardeña project following closing of the Transaction (Golden estimates that operating and continued development costs at Velardeña will be funded from the sale of doré and concentrates produced from ongoing Velardeña operations);



•

Approximately $12.0 million during the remainder of 2011 to fund the drilling of two targets in Argentina, three in Peru and four in Mexico, and on other generative exploration activities and property holding costs related to our portfolio of exploration properties conducted through our principal exploration offices located in South America and Mexico. Additional spending is possible for early and advanced stage drilling programs, depending on the success of our targeted exploration program and generative exploration activities;



•

Approximately $9.0 million during the remainder of 2011 on debt service and the reduction of other short term liabilities relating to obligations of ECU acquired in the Transaction;



•

Approximately $7.0 million during the remainder of 2011 on general and administrative costs;



•

Approximately $2.0 million during the remainder of 2011 on working capital and other general corporate purposes.

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        We plan to fund the expenditures described above from our cash and investment balances at March 31, 2011 of $106.1 million and from approximately $0.3 million from royalties and other income through the end of 2011. Based on these projections we would end the year 2011 with cash and investment balances of approximately $30.0 to $33.0 million.

        The actual amount that we spend through the end of 2011 may vary significantly from the amounts specified above, and will depend on a number of factors, including the results of our continued exploration activities and project assessment work at El Quevar and our other exploration properties, and the results of continuing operations and further development work and project assessment work at Velardeña. There can be no assurance the expenditures planned for El Quevar or Velardeña will demonstrate the economic viability of either project.

        If economic studies at either the El Quevar or Velardeña projects are positive, significant additional capital would be required to complete development and plant construction associated with the projects. To fund completely either project or other exploration drilling programs beyond 2011 we will have to raise additional capital or enter into other financing arrangements. The Sentient Group has expressed an interest in investing further capital in the combined company in order to maintain its current ownership of approximately 19%, which could generate approximately $[    •    ] million in additional cash at $[    •    ] per share, which was Golden closing stock price on the NYSE Amex on [    •    ], 2011. However, no agreement has been reached with Sentient, and it is uncertain whether an additional investment by Sentient will occur, the number of Golden shares that would be purchased, or the amount of cash that would be generated by the investment if it were to occur. There can be no assurance that we will be successful in raising additional capital or obtaining financing in the future on terms acceptable to us or at all. If we are unable to obtain additional capital or alternative financing arrangements during 2011 or beyond, the potential development of the El Quevar or Velardeña projects could be delayed following the completion of economic studies and we may have to significantly reduce spending on other exploration projects to preserve cash.

Comparative Historical and Pro Forma Per Share Data

        The following tables set forth historical and pro forma per share data for Golden and historical per share data for ECU. The Golden historical data have been derived from, and should be read together with, the audited consolidated financial statements of Golden and the related notes thereto included elsewhere in this proxy statement and the unaudited condensed consolidated financial statements of Golden and the related notes thereto contained in Golden's Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2011 incorporated by reference into this proxy statement. The Golden pro forma data have been derived from the unaudited condensed combined pro forma financial data of Golden included elsewhere in this proxy statement. See "Additional Information—Where Stockholders Can Find More Information About Golden" and "—Where Stockholders Can Find More Information About ECU."

        This summary of comparative historical and pro forma per share data is being provided for illustrative purposes only and is not necessarily indicative of the results that would have been achieved had the Transaction been completed during the period presented, nor are they necessarily indicative of any future results. Golden and ECU may have performed differently had the Transaction occurred prior to the period presented. You should not rely on the pro forma per share data presented as being indicative of the results that would have been achieved had Golden and ECU been combined during the period presented or of the future results of Golden following the Transaction.

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        The following tables presents certain historical and pro forma per share data for Golden:

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INFORMATION CONCERNING GOLDEN

Overview

        We are a mineral exploration company with a diversified portfolio of precious metals and other mineral exploration properties located in or near the traditional precious metals producing regions of Mexico and South America. We are currently focused on advancement of our El Quevar silver project in northwestern Argentina and engaged in additional drilling, metallurgical analysis and other advanced exploration work at El Quevar. In addition to El Quevar, we own and control a portfolio of approximately 45 exploration properties located primarily in Mexico and South America. Our 100% controlled Zacatecas silver and base metals project in Mexico is in an advanced stage of exploration. We also have reconnaissance properties on which we are conducting preliminary sampling and geological analysis to determine the best potential areas for more detailed exploration. Our principal offices are located in Golden, Colorado at 350 Indiana Street, Suite 800, Golden, CO 80401, and our telephone number is (303) 839-5060. We also maintain exploration offices in Argentina, Mexico, Peru and Chile.

Golden Documents Incorporated by Reference

        The SEC allows Golden to incorporate by reference information into this proxy statement. This means that Golden may disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be a part of this document, except for any information that is superseded by information that is included directly in this document or incorporated by reference subsequent to the date of this document. See "Additional Information—Where Stockholders Can Find More Information About Golden" on page [    •    ].

El Quevar

        Our El Quevar silver project is located near Nevado Peak in the San Antonio de los Cobres municipality, Salta province, in the Altiplano region of northwestern Argentina.

        The Yaxtché deposit is one of three primary targets currently identified at the El Quevar project. As of July 1, 2011, Golden has completed approximately 80,270 meters of diamond drilling in 330 drill holes. Of these holes, 227 were drilled to test the main Yaxtché zone for potential mineralization, with about 70% of the holes intersecting significant silver mineralization. Golden's work indicates that the Yaxtché central zone is at least 650 meters in strike length, with other drilling results to the east and west indicating a total length of more than 1,500 meters, and between 40 to 150 meters in width. Golden's drilling further indicates that the silver mineralization is continuous laterally and to depths of 350 meters below surface in the main area.

        As of July 1, 2011, we have also completed more than 820 meters of development drifting at El Quevar and have advanced approximately 600 meters along strike in the central Yaxtché zone. The drifting has encountered more than 40 mineralized structures believed to be tension faults that were not anticipated in the current modeling of the El Quevar deposit, in which mineral concentrations are modeled to follow the alteration envelope. Although the structures are narrow, generally less than a quarter of a meter in width, results from detailed sampling show that the structures tend to be of substantial grade, typically in excess of one kilogram per tonne of silver. We are conducting uniform channel sampling of the structures and the alteration envelope. Our evaluation of the features seen in the development drift should contribute to the understanding of these newly discovered structures and provide further information regarding confirmation of the mine model. We decided to delay completion of a NI 43-101 compliant Preliminary Economic Assessment and a planned mid-year 2011 resource update to allow further work to assess the impact that these newly discovered structures may have on the mining plan and global El Quevar resource.

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        As part of this effort, Golden is currently examining the bulk mining potential of the Yaxtché zone at El Quevar. Preliminary engineering indicates that an open pit could be feasible on the eastern end of the Yaxtché zone and Golden is performing an optimization analysis of the potential pit. Following completion of these analyses, Golden will examine the potential for bulk underground mining of the higher grade western zone. We may reduce our level of activity in advancing the drift until this work has been completed, as the open pit would encompass the area through which the drift would advance. Golden has targeted the fourth quarter 2011 for a resource update based on the bulk mining studies. If these efforts are successful, Golden would proceed with a NI 43-101 compliant Preliminary Economic Assessment in the first half of 2012.

        In addition to further in-fill drilling on the Yaxtché deposit, we have completed a first-phase drill program on the ManiSub target, which is located approximately 500 meters southwest of the Yaxtché deposit, and may also conduct additional drilling on the Carmen target, located approximately 500 meters north of the Yaxtché deposit.

Golden Comparative Market Prices

        Shares of Golden common stock are traded on the NYSE Amex under the symbol "AUMN" and on the Toronto Stock Exchange under the symbol "AUM." As of [    •    ], 2011, [    •    ] shares of common stock were outstanding, and we had approximately [    •    ] shareholders of record. On June 23, 2011, being the day prior to the public announcement of the Transaction, the closing price per share for our common stock as reported by NYSE Amex was $20.22 and as reported by the Toronto Stock Exchange was Cdn$19.38 ($19.77 as converted into U.S. dollars) and on [    •    ], 2011, the closing price per share was $[    •    ] on the NYSE Amex and Cdn$[    •    ] on the TSX ($[    •    ] as converted into U.S. dollars).

        Our common stock began trading on the NYSE Amex on March 19, 2010, and began trading on the Toronto Stock Exchange on July 16, 2009. The following table sets forth, for the periods indicated, the high and low sales prices per share of Golden common stock as reported by the NYSE Amex and the Toronto Stock Exchange: