**Exhibit10.4**

**ExecutionVersion**

**OPTIONAGREEMENT**

**Enteredinto as of September 25, 2006betweenAPEX SILVER MINES LIMITEDandSUMITOMO CORPORATION**

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**TABLE OF CONTENTS**
|                                    | ** ** | ** **                                         | ** ** | **Page** | ** ** |
|------------------------------------|------------|----------------------------------------------------|------------|----------|------------|
|                               |       |                                               |       |     |       |
| ARTICLE I DEFINITIONS              |       | 2                                                  |       |
| Section 1.1                        |       | Defined Terms                                      |       | 2        |       |
| Section 1.2                        |       | Definitions from Purchase and Sale Agreement       |       | 6        |       |
|                               |       |                                               |       |     |       |
| ARTICLE II GENERAL                 |       | 6                                                  |       |
| Section 2.1                        |       | Active and Reserve Assets                          |       | 6        |       |
|                               |       |                                               |       |     |       |
| ARTICLE III ACTIVE ASSET OPTION    |       | 7                                                  |       |
| Section 3.1                        |       | Grant of Active Asset Option                       |       | 7        |       |
| Section 3.2                        |       | Active Asset Option Term                           |       | 7        |       |
| Section 3.3                        |       | Exercise of Active Asset Option                    |       | 7        |       |
| Section 3.4                        |       | Payment with respect to each Optioned Active Asset |       | 8        |       |
| Section 3.5                        |       | Failure to Exercise Active Asset Option            |       | 9        |       |
| Section 3.6                        |       | Cessation of an Active Asset; Third-Party Sale     |       | 9        |       |
| Section 3.7                        |       | Access to Records                                  |       | 10       |       |
|                               |       |                                               |       |     |       |
| ARTICLE IV RESERVE ASSET OPTION    |       | 11                                                 |       |
| Section 4.1                        |       | Grant of Reserve Asset Option                      |       | 11       |       |
| Section 4.2                        |       | Reserve Asset Option Term                          |       | 11       |       |
| Section 4.3                        |       | Exercise of Option                                 |       | 11       |       |
| Section 4.4                        |       | Payment for Optioned Reserve Assets                |       | 12       |       |
| Section 4.5                        |       | Failure to Exercise Reserve Asset Option           |       | 13       |       |
| Section 4.6                        |       | Cessation of a Reserve Asset; Third-Party Sale     |       | 13       |       |
| Section 4.7                        |       | Access to Records                                  |       | 14       |       |
|                               |       |                                               |       |     |       |
| ARTICLE V TERM AND TERMINATION     |       | 14                                                 |       |
| Section 5.1                        |       | Term                                               |       | 14       |       |
| Section 5.2                        |       | Effect of Termination                              |       | 15       |       |
|                               |       |                                               |       |     |       |
| ARTICLE VI FAILURE TO MAKE PAYMENT |       | 15                                                 |       |
| Section 6.1                        |       | Failure to Make Holding Cost Payment               |       | 15       |       |
|                               |       |                                               |       |     |       |
| ARTICLE VII ADDITIONAL PROVISIONS  |       | 15                                                 |       |
| Section 7.1                        |       | Entire Agreement                                   |       | 15       |       |
| Section 7.2                        |       | Confidentiality                                    |       | 15       |       |
| Section 7.3                        |       | Governing Law; Language                            |       | 16       |       |
| Section 7.4                        |       | Dispute Resolution                                 |       | 16       |       |
| Section 7.5                        |       | Headings                                           |       | 16       |       |
| Section 7.6                        |       | Notices                                            |       | 16       |       |
| Section 7.7                        |       | Severability                                       |       | 17       |       |
|                                    |            |                                                    |            |          |            |  |  |

 

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|              | ** ** | ** **                    | ** ** | **Page** | ** ** |
|--------------|------------|-------------------------------|------------|----------|------------|
|         |       |                          |       |     |       |
| Section 7.8  |       | Amendment; Waiver             |       | 17       |       |
| Section 7.9  |       | Assignment and Binding Effect |       | 17       |       |
| Section 7.10 |       | No Benefit to Others          |       | 18       |       |
| Section 7.11 |       | No Consequential Damages      |       | 18       |       |
| Section 7.12 |       | Counterparts                  |       | 18       |       |
| Section 7.13 |       | Interpretation                |       | 18       |       |
| Section 7.14 |       | Rules of Construction         |       | 19       |       |
|              |            |                               |            |          |            |  |  |

 

Appendix A          Active Assets

Appendix B           ReserveAssets

 

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**OPTION AGREEMENT**

This Option Agreement is entered into as of September25, 2006 (the “Effective Date”), by and between:

**APEX SILVER MINES LIMITED**,an exempted company limited by shares duly incorporated and validly existingunder the Laws of the Cayman Islands, British West Indies (“Apex”), withits registered office at the offices of Walkers SPV Limited, P.O. Box 908GT,Walker House, Mary Street, George Town, Grand Cayman, Cayman Islands, BritishWest Indies; and 

**SUMITOMO CORPORATION**,a corporation duly organized and validly existing under the Laws of Japan (“Sumitomo”),with its headquarters at 1-8-11, Harumi, Chuo-ku, Tokyo 104-8610,Japan.

Apex and Sumitomo are sometimes referred to hereinindividually as a “Party” and collectively as the “Parties.”  Capitalized terms used and not otherwisedefined in this Agreement have the respective meanings ascribed thereto inARTICLE I.

**RECITALS**

A.            Pursuant tothe Purchase and Sale Agreement, dated as of the date hereof (the “Purchaseand Sale Agreement”), Sumitomo, among other things, acquired (1) 100%of the issued and outstanding share capital of New Sweden 1, which on theClosing Date owned 35% of the issued and outstanding share capital of MineraSan Cristóbal S.A., a *sociedadanónima* organizedunder the Laws of Bolivia (“MSC”), (2) 100% of the issued andoutstanding share capital of New Sweden 2, which on the Closing Date owned 35%of the issued and outstanding quotas of Apex Metals Marketing GmbH, a *Gesellschaft mit beschränkter Haftung*organized under the Laws of Switzerland (“New Metals”), and (3) 35%of the issued and outstanding share capital of Apex Silver Finance Ltd., an exempted company limited by sharesincorporated under the Laws of the Cayman Islands, British West Indies (“NewCayman”) (collectively, the “Acquisition”).

B.            In connection with the Acquisition, Sumitomo desires toobtain, and Apex is willing to grant to Sumitomo, an option to acquire up to a35% interest (but not less than 20%) in certain mineral exploration assets ofApex (or its Subsidiaries) pursuant to the terms and conditions set forthbelow.

**agreement**

In consideration of themutual promises, covenants, and agreements set forth herein, the Purchase andSale Agreement and other good and valuable consideration, the receipt andsufficiency of which are hereby acknowledged, the Parties hereby agree asfollows:

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** **

# **ARTICLE I****DEFINITIONS**

## Section 1.1                Defined Terms.  For purposes of this Agreement, the followingterms have the following meanings:

“Acquisition” has the meaning specified in therecitals.

“Active Asset” means Apex’s (or itsSubsidiary’s) Rights with respect to an Exploration Property set forth inAppendix A attached hereto.

“Active Asset Cessation/Sale Notice” has themeaning specified in Section 3.6(a). 

“Active Asset Option” has the meaning specifiedin Section 3.1.

“Active Asset Option Notice” has the meaningspecified in Section 3.3(a).

“Active Asset Option Term” hasthe meaning specified in Section 3.2.

“Active Asset Payment” has the meaningspecified in Section 3.4(a).

“Active Offered Terms” has the meaningspecified in Section 3.6(c).

“Active Retained Interest” has the meaningspecified in Section 3.6(b).

“Active Third-Party Sale” has the meaningspecified in Section 3.6(a).

“Affiliate” means, with respect to any Person,any other Person that directly, or indirectly through one or moreintermediaries, Controls, is Controlled by, or is under common Control with,the Person in question.

“Agreement” means this Option Agreement(including the Appendices attached hereto).

“Apex” has the meaning specified in thepreamble.

“Asset Development Documents” means allmaterial documents, agreements, accounting records, and financial statements inApex’s possession related to an Exploration Property.

“Business Day” means any day other than Saturday,Sunday, and a day on which banks in New York, New York, U.S.A. or Tokyo, Japanare required or permitted to close.

“Confidential Information” has the meaningspecified in Section 7.2.

“Definitive Exploration Property Agreements”has the meaning specified in Section 3.3(b).

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“Development Costs” means costs paid to thirdparties incurred after the acquisition of an Exploration Property to evaluatethe feasibility of developing and conducting mining operations on suchproperty, provided that Development Costs shall not include any Holdings Costs.

“Dispute Resolution Agreement” means thatcertain Dispute Resolution Agreement, dated as of the date hereof, by and amongApex, Apex Sweden, Apex Luxembourg, Service Company, Sumitomo, NewSweden 1, New Sweden 2, MSC, New Metals, and New Cayman.

“Dollar” or “Dollars” means the lawfulcurrency of the United States of America.

“Effective Date” has the meaning specified inthe preamble.

“Exploration Costs” means all costs andexpenses incurred in conducting exploration and prospecting activities on or inconnection with an asset including the preparation of feasibility studies, theactive pursuit of required Government Approvals and the performance of requiredenvironmental protection or reclamation obligations, the building, maintenance,and repair of roads, drill site preparation, drilling, tracking, sampling,trenching, digging test pits, shaft sinking, acquiring, diverting, and/ortransporting water necessary for exploration, logging of drill holes and drillcore, completion and evaluation of geological, geophysical, geochemical, orother exploration data, and preparation of interpretive reports, and surveyingand laboratory costs and charges (including assays or metallurgical analysesand tests).

“Exploration Entity” means an Entity as may bepermitted to be formed in any given jurisdiction, formed to pursue thedevelopment of a given Exploration Property.

“Exploration Property” has the meaningspecified in Section 2.1(a).

“GAAP” means generally accepted accountingprinciples as used in the United States of America.

“Holding Costs” means the periodic and otherordinary and necessary costs of owning, leasing, licensing, maintaining, orotherwise holding an Exploration Property or the Rights associated therewithincluding property taxes, annual minimum lease, license, or royalty payments,insurance, costs for providing security for persons and equipment on suchproperty, the costs of routine land, buildings, and equipment maintenance, andinterest on debt incurred to acquire such Exploration Property or Rights.

“Holding Costs Payment” has the meaningspecified in Section 3.6(b).

“Interest” has the meaning specified in Section3.1.

“Interest Ratio” has the meaning specified inthe MSC Shareholder Agreement.

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“Moody’s” means Moody’s Investors Service, Inc.and any successor thereto, so long as such successor is a “nationallyrecognized statistical rating organization” registered with the Securities andExchange Commission of the United States of America.

“MSC” has the meaning specified in therecitals.

“MSC Shareholders Agreement” means that certainMSC Shareholders Agreement, dated as of the Closing Date, among Apex Sweden,Apex Luxembourg, New Sweden 1 and MSC.

“Optioned Active Asset” has the meaningspecified in Section 3.3(a).

“Optioned Asset Historical Cost” means thedocumented or supported aggregate historical costs incurred by Apex withrespect to the Optioned Active Asset(s) or the Optioned Reserve Asset(s), asapplicable.  Such historical costs shallinclude Exploration Costs, Holding Costs, and all other related costs,including reasonably allocated overhead costs related to such asset.

“Optioned Reserve Asset” has the meaningspecified in Section 4.3(b).

“Party” or “Parties” has the meaningspecified in the preamble.

“Payment Date” has the meaning specified inSection 6.1.

“Purchase and Sale Agreement” has the meaningspecified in the recitals.

“Qualified Third Party” means an Entity the non-credit-enhancedlong-term senior unsecured debt of which is rated at least the lesser of(i) BBB- by S&P or Baa3 by Moody’s, and (ii) the creditrating of the non-credit-enhanced long-term senior unsecureddebt of Sumitomo as provided by S&P or Moody’s as of the date of thetransfer, sale, or other disposition by Sumitomo (or its Subsidiary) of itsdirect or indirect equity interests in an Exploration Entity to such Entity.

“Reserve Asset” means Apex’s (or itsSubsidiary’s) Rights with respect to an Exploration Property set forth inAppendix B attached hereto or deemed to be a Reserve Asset in accordancewith the terms hereof.

“Reserve Asset Cessation/Sale Notice” has themeaning specified in Section 4.6(a). 

“Reserve Asset Option”has the meaning specified in Section 4.1. 

“Reserve Asset Option Notice” has the meaningspecified in Section 4.3(b).

“Reserve Asset Option Term” has the meaningspecified in Section 4.2. 

“Reserve Asset Trigger Notice” has the meaningspecified in Section 4.3(a).

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“Reserve Definitive Exploration Property Agreements”has the meaning specified in Section 4.3(c).

“Reserve Offered Terms” has the meaningspecified in Section 4.6(c). 

“Reserve Retained Interest” has the meaningspecified in Section 4.6(b).

“Reserve Third-Party Sale” has themeaning specified in Section 4.6(a).

“Review Documents” has the meaning specified inSection 3.2.

“Rights” has the meaning specified in Section2.1(a).

“S&P” means Standard & Poor’s RatingsServices, a division of The McGraw-Hill Companies, Inc and any successorthereto so long as such successor is a nationally recognized statistical ratingorganization registered with the Securities and Exchange Commission of theUnited States of America.

“Subsidiary” means with respect to any Person(other than MSC, New Metals and New Cayman as same apply to Apex):

(a)           a corporation a majority in votingpower of whose share capital with voting power, under ordinary circumstances,to elect directors is, at the date of determination thereof, directly orindirectly, owned by such Person, by a Subsidiary of such Person, or by suchPerson and one or more Subsidiaries of such Person,

(b)           a partnership or limited liabilitycompany in which such Person or a Subsidiary of such Person is, at the date ofdetermination thereof, (i) in the case of a partnership, a general partnerof such partnership with the power affirmatively to direct the policies andmanagement of such partnership or (ii) in the case of a limited liabilitycompany, the managing member or, in the absence of a managing member, a memberwith the power affirmatively to direct the policies and management of suchlimited liability company, or

(c)           any Entity (other than a corporation,partnership, or limited liability company) in which such Person, a Subsidiaryof such Person, or such Person and one or more Subsidiaries of such Person,directly or indirectly, at the date of determination, has (i) the power toelect or direct the election of a majority of the members of the governing bodyof such Person or (ii) in the absence of such a governing body, at least amajority ownership interest.

“Sumitomo” has the meaning specified in thepreamble.

“Sumitomo Interestholders” has the meaningspecified in the MSC Shareholder Agreement.

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“Term” has the meaning specified in Section5.1(a).

“US$” means Dollars.

## Section 1.2                Definitions from Purchase andSale Agreement.  Undefined capitalized terms used herein havethe respective meanings set forth in the Purchase and Sale Agreement.

# **ARTICLE II****GENERAL**

## Section 2.1                Activeand Reserve Assets.

### (a)           Appendices A and B attachedhereto set forth the ownership rights (the “Rights”) of Apex (or itsSubsidiaries) with respect to each Active Asset or Reserve Asset set forththerein (each an “Exploration Property”).  Apex represents and warrants that it, or itsSubsidiary, own such Rights.  Sumitomoacknowledges that the Rights may be subject to transfer restrictions or otherlimitations (i.e. rights of first refusal) and in connection therewith,Sumitomo’s rights under this Agreement are subject thereto.  Subject to Section 3.6 and Section 4.6, Apexfurther covenants, represents and warrants that, to the extent within thecontrol of Apex, neither Apex nor any applicable Affiliate of Apex shall grantany acquisition rights to third-parties with respect to the Rights or theExploration Properties other than Sumitomo during the Term. Notwithstanding anything herein to the contrary, in no event shall theoption rights granted hereunder apply to any property right or Contract towhich Apex (or any of its Subsidiaries) is a party or any of its rights orinterests thereunder if, and for so long as, the grant of such rights shallconstitute or result in (i) the abandonment, invalidation, orenforceability of any right or interest of Apex (or its Subsidiaries) thereinor (ii) a breach or termination pursuant to the terms of, or a defaultunder, any such property right or Contract; provided, however,that such grant shall apply immediately at such time as the condition causingsuch abandonment, invalidation, or unenforceability shall be remedied, and tothe extent severable, shall apply immediately to any portion of such propertyright or Contract that does not result in the consequences specified in clause(i) or (ii) of this Section 2.1(a).

### (b)           Apex shall have the right atany time, and from time to time prior to the commencement of an Active AssetOption Term relating to a specified Active Asset, to reclassify such ActiveAsset as a Reserve Asset and *vice versa*and Appendices A and B shall be amended accordingly by Apex without furtheraction of the Parties under Section 7.8; provided, however, thatno such reclassification shall be made on or after 18 months after theEffective Date or with respect to an asset if an Active Asset Option Notice ora Reserve Asset Option Notice, as applicable, has been delivered with respectto such asset in accordance with the terms of this Agreement.

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# **ARTICLEIIIACTIVE ASSET OPTION**

 

## Section 3.1                Grantof Active Asset Option. Apex hereby grants to Sumitomo the option (the “Active Asset Option”)to acquire from time to time during the Term and on the terms and conditionsset forth in this ARTICLE III, an undivided interest of not less than 20% butnot more than 35% (an “Interest”) in one or more of the Active Assets.

## Section 3.2                ActiveAsset Option Term.  The “Active Asset Option Term” for anyActive Asset shall commence on the date that Sumitomo receives the AssetDevelopment Documents for such Active Asset and shall terminate at 11:59 P.M.(Denver, Colorado, U.S.A. time) on the date that is 60 days after the dateSumitomo receives the Asset Development Documents for such Active Asset.  Apex shall deliver the Asset DevelopmentDocuments relating to all of the Active Assets to Sumitomo no later than 22months after the Effective Date.  In theevent that Apex (or its Subsidiaries) comes in possession of an AssetDevelopment Document not previously in its possession after the commencement ofthe Active Asset Option Term, or in the event Apex (or its Subsidiaries)creates an Asset Development Document after the commencement of the ActiveAsset Option Term, Apex shall promptly deliver such document to Sumitomo, butthe existence of such document shall not extend the Active Asset OptionTerm.  In addition, Sumitomo acknowledgesand agrees that some Asset Development Documents may be made available toSumitomo for review but not physically delivered (“Review Documents”).  Apex shall provide Sumitomo prompt writtennotice of the existence of Review Documents and the location thereof, but thereceipt of such notice and the existence of such Review Documents shall notextend the Active Asset Option Term.

## Section 3.3                Exercise of Active AssetOption.

### (a)           If Sumitomoelects to exercise any Active Asset Option, Sumitomo shall deliver a writtennotice (the “Active Asset Option Notice”) to Apex prior to theexpiration of such Active Asset Option Term relating to such Active Asset.  The Active Asset Option Notice shall setforth the Active Asset in which Sumitomo elects to acquire an Interest (the “OptionedActive Asset”) and the amount of the Interest Sumitomo wishes to acquire,which in no case shall be less than 20% nor more than 35%, in each such case anOptioned Active Asset.

### (b)           Commencing upon receipt by Apex ofthe Active Asset Option Notice, Apex and Sumitomo shall (i) jointlydetermine a mutually acceptable structure for the acquisition of Interests inthe Optioned Active Assets, and (ii) enter into acquisition documents withrespect thereto that are on terms and conditions reasonably acceptable to theParties (including, among other documents, a shareholders or joint ventureagreement providing for the contribution by each party of its *pro rata* share of future operating andcapital costs of the Optioned Active Assets) (the “Definitive ExplorationProperty Agreements”).  TheDefinitive Exploration Property Agreements shall include provisions for(A) rights of first refusal with respect to a Party’s transfer of all orpart of its interest therein, (B) the contribution by each party of its *pro rata* share of future operating andcapital costs of the Optioned Active Assets, (C) dilution, so that ifeither Party fails to contribute its proportionate share, the other Party shallhave the right to contribute the

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### non-contributing party’s share againstthe issuance of additional beneficial interests (in shares, quotas, membership,or partnership interest or other comparable designation) to the contributingParty to reflect the adjusted proportionate holdings resulting from suchcontribution(s) (and non-contribution, as applicable), (D) loss ofrights so that at such time a Party’s beneficial interest in an ExplorationEntity falls below 25% as a result of clause (C) of this Section 3.3(b),such Party shall have no further rights with respect to the management of suchExploration Entity or the Optioned Active Asset it is developing except theright to have a director on the Board of Exploration Entity until the Party'sbeneficial interest falls below 20%, and (E) provisions, on such terms asthe Parties may mutually agree, similar to ARTICLE II, Section 3.2, Section3.3, Section 5.1 and Section 7.7 of the MSC Shareholders Agreement.  Apex shall cause any of its Subsidiarieswhich have rights in the applicable Optioned Active Asset to enter into theDefinitive Exploration Property Agreements to the extent reasonably requiredfor Sumitomo to effectively acquire its Interest in the Optioned ActiveAsset.  Notwithstanding the foregoing,Sumitomo may at any time prior to the execution of the Definitive ExplorationProperty Agreements elect, by written notice to Apex, not to acquire an interestin one or more Optioned Active Assets to which the Definitive ExplorationProperty Agreements relate, in which event (X) such Optioned Active Assetsshall cease to be subject to this Agreement, and (Y) Sumitomo shallreimburse Apex for reasonable out-of-pocket expenses incurred byApex in connection with the negotiation of the Definitive Exploration PropertyAgreement including attorney’s and other consultant fees.

## Section 3.4                Payment with respect to eachOptioned Active Asset.

### (a)           Inconsideration for each Optioned Active Asset, Sumitomo shall, in eachapplicable Definitive Exploration Property Agreement, agree to contribute toeach Exploration Entity operating the respective Optioned Active Asset theDollar amount, in cash, equal to 100% of all costs incurred by the ExplorationEntity since its establishment until such time Sumitomo’s contributions to suchentity shall equal an amount which, when divided by a number equal to the sumof (i) Sumitomo’s said contributions plus (ii) the OptionedAsset Historical Cost incurred up to the effective date of such DefinitiveExploration Property Agreement, equals the same percentage as the Interest insuch Optioned Active Asset that Sumitomo is acquiring (the “Active AssetPayment”).

### (b)           Sumitomo and Apex hereby acknowledge and agree thatif Sumitomo (or its Subsidiary) transfers, sells, or otherwise disposes of itsdirect or indirect equity interests in an Exploration Entity prior to paymentin full of the Active Asset Payment as set forth in Section 3.4(a), thenSumitomo (or its Subsidiary) shall, within five Business Days of the date onwhich Sumitomo or its Subsidiaries ceases to own such equity interest, pay Apex(or its Subsidiary) an amount, in cash, equal to the outstanding unpaid amountof the Active Asset Payment which payment shall satisfy the obligation underSection 3.4(a).  Notwithstanding theforegoing and subject to any applicable rights of first refusal, if Sumitomo orits Subsidiary transfers, sells or otherwise disposes of all, but not less thanall, of its direct or indirect equity interests in such Exploration Entity to a

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### Qualified Third Party, and if such QualifiedThird Party expressly assumes all of Sumitomo’s obligations under thisAgreement in a writing delivered to Apex (or its Subsidiary), then Sumitomoshall be released of its obligations with respect to the applicable ActiveAsset arising from and after the completion of such transfer, except for suchobligations arising out of events or circumstances that occurred prior to thecompletion of such transfer, whether occurring before, at, or after thecompletion of such transfer, and only to the extent such obligations have beenassumed by the Qualified Third Party.  

## Section 3.5                Failureto Exercise Active Asset Option

.  In the event that Sumitomo doesnot elect to exercise an Active Asset Option with respect to a specific ActiveAsset during the Active Asset Option Period relating to such Active Asset inaccordance with the terms and conditions of this ARTICLE III, then Sumitomo’srights with respect to such Active Asset as set forth in this ARTICLE III shallterminate and have no further force or effect, and, notwithstanding anything tothe contrary in this Agreement, the Parties hereto shall have no liability,responsibility, or obligation, whatsoever, to the each other in respect of thisARTICLE III with respect to such Active Asset.

## Section 3.6                Cessationof an Active Asset; Third-Party Sale.

###  

### (a)           If, prior tothe end of the Term and prior to Sumitomo’s submission of an Active Asset OptionNotice with respect to any Active Asset, Apex either (i) elects to ceasethe exploration or development of an Active Asset still subject to the ActiveAsset Option or (ii) agrees (subject to this Agreement) to sell aninterest in an Active Asset still subject to the Active Asset Option to anunaffiliated third party (an “Active Third-Party Sale”), then,promptly after such decision or agreement, Apex shall provide Sumitomo writtennotice of same (the “Active Asset Cessation/Sale Notice”) together with theAsset Development Documents relating to such Active Asset, to the extent notalready delivered.  Sumitomo shall havethe right to acquire all or part of the subject Active Asset on the terms andconditions set forth in Section 3.6(b) and Section 3.6(c).  

### (b)           If the Active Asset Cessation/Sale Notice statesthat Apex intends to cease the exploration or development of an Active Assetstill subject to the Active Asset Option, then Apex shall indicate in theActive Asset Cessation/Sale Notice the percentage interest of the interest insuch Active Asset that Apex shall have the right to retain (the “ActiveRetained Interest”); provided, however, that such ActiveRetained Interest shall not exceed 35% of the interest in such ActiveAsset.  Sumitomo shall have 60 days fromthe date of receipt of the Active Asset Cessation/Sale Notice and the relatedAsset Development Documents to elect to either (i) acquire the ActiveAsset, other than the Active Retained Interest therein, on the terms,conditions, and procedures set forth in Section 3.3(b), or (ii) requestthat such Active Asset be deemed a Reserve Asset.  Any such election shall be made by writtennotice to Apex specifying whether Sumitomo is electing to acquire such AcquiredAsset or to deem it a Reserve Asset.  Inaddition:

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###  

#### (I)            If Sumitomo elects to acquire theapplicable percentage interest of such Active Asset, then the purchase pricefor such interest shall be the Dollar amount, in cash, equal to the product of(i) the percentage interest of such Active Asset to be acquired bySumitomo and (ii) Optioned Asset Historical Costs incurred by Apex forsuch Active Asset up to the date of Sumitomo’s payment of such purchaseprice.  

#### (II)           If Sumitomo elects to deem any suchActive Asset a Reserve Asset, such Active Asset shall thereafter be treated asa Reserve Asset subject to the provisions of ARTICLE IV.  Sumitomo shall be responsible for all HoldingCosts with respect to such asset from the date such asset is designated aReserve Asset until the earlier of (A) the termination of this Agreementor (B) the date on which Sumitomo acquires an Interest in such asset inaccordance with the terms hereof (the “Holding Costs Payment”).  In connection therewith, Apex, on a monthlybasis, shall provide Sumitomo an invoice that sets forth the amount payable bySumitomo with respect such Holding Costs along with reasonable supportingdocumentation thereof.  All amountsinvoiced shall be payable by Sumitomo no later than five Business Days afterinvoice receipt.  Payment of any suchHolding Costs that are outstanding (including any interest accrued thereon andwhether invoiced or not) shall be a condition to the closing of Sumitomo’sacquisition of an Interest in such asset, to the extent Sumitomo elects toacquire an Interest in accordance with ARTICLE IV.

### (c)           If the ActiveAsset Cessation/Sale Notice states that Apex intends to enter into an ActiveThird-Party Sale, then Apex shall indicate in the Active AssetCessation/Sale Notice the terms and conditions on which such Active Asset isproposed to be sold to a third party (the “Active Offered Terms”)(including the percentage interest to be sold, sale price, and applicable timeperiod in which the transaction shall close). Sumitomo shall have 30 Business Days from the date of receipt of theActive Asset Cessation/Sale Notice and the related Asset Development Documentsto elect to acquire such interest in the applicable Active Asset on the ActiveOffered Terms.  Apex may sell such ActiveAsset to a third-party on the Active Offered Terms within 120 days of theend of such 30 Business Day period or within 120 days of Sumitomo’s failure toconsummate the transaction on the Active Offered Terms (including applicablerequired time periods with respect thereto) after having made an election to doso.  In the event Apex does not completesuch a sale to a third party on the Active Offered Terms, the Active Assetshall, at the election of Apex, be deemed either an Active Asset or a ReserveAsset.

## Section 3.7                Access to Records.  Commencing on the Effective Date until theend of the Term (except with respect to those Active Assets with respect towhich the Active Asset Option has terminated), Apex shall afford to Sumitomoand its business, accounting, legal, engineering and other representatives, aswell as their respective officers and employees, reasonable access, uponreasonable notice, to its documents, agreements, accounting records, and

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## financial statements applicable to, and tothe physical properties comprising, the Active Assets and shall permit Sumitomoand such representatives to make such tests, including soil and other fieldtests, of such Active Assets as Sumitomo may reasonably request.  

# **ARTICLE IV****RESERVEASSET OPTION**

## Section 4.1                Grantof Reserve Asset Option.  Apex hereby grants to Sumitomo the option(the “Reserve Asset Option”) to acquire, from time-to-timeduring the Term and on the terms and conditions set forth in this ARTICLE IV,an Interest in one or more of the Reserve Assets.  

## Section 4.2                ReserveAsset Option Term.  The “Reserve Asset Option Term” withrespect to any Reserve Asset shall commence on the date (after delivery of theapplicable Reserve Asset Trigger Notice) Sumitomo receives the AssetDevelopment Documents (taking into account any Asset Development Documentsprovided or reviewed by Sumitomo in accordance with Section 4.3 prior to suchdate) with respect to such Reserve Asset and shall terminate at 11:59 p.m.(Denver, Colorado time) on the date that is 60 days after Sumitomo receivessuch documents.  In the event that Apex(or its Subsidiaries) comes in possession of an Asset Development Document notpreviously in its possession after the commencement of the Reserve Asset OptionTerm, or in the event Apex (or its Subsidiaries) creates an Asset Development Documentafter the commencement of the Reserve Asset Option Term, Apex shall promptlydeliver such document to Sumitomo, but the existence of such document shall notextend the Reserve Asset Option Term.  Inaddition, Sumitomo acknowledges and agrees that Apex may provide Sumitomo withReview Documents.  Apex shall provideSumitomo prompt written notice of the existence of Review Documents and thelocation thereof, but the receipt of such notice and the existence of suchReview Documents shall not extend the Reserve Asset Option Term.

## Section 4.3                Exercise of Option.

### (a)           Apex shall provide Sumitomowritten notice promptly after Apex has expended in excess of US$200,000 (asdetermined from the Effective Date) in Development and/or Exploration Costswith respect to a Reserve Asset, and Sumitomo may at any time during the Termprovide a written notice to Apex requesting that Apex deliver to Sumitomo allAsset Development Documents relating to a specified Reserve Asset (either suchnotice being a “Reserve Asset Trigger Notice”).  Apex shall provide Sumitomo with all AssetDevelopment Documents relating to such Reserve Asset as soon as practicableafter delivery of the Reserve Asset Trigger Notice. For clarity, Sumitomo may request to reviewdocuments related to any of the Reserve Assets at any time during the Term ofthis agreement, whether or not a Reserve Asset Trigger Notice has beendelivered by Apex, for the purpose of determining Sumitomo’s desire to presenta Reserve Asset Option Notice under the terms of this Section 4.3(a).

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###  

### (b)           At any timeprior to the end of any Reserve Asset Option Term, Sumitomo may elect toexercise the Reserve Asset Option with respect to the Reserve Asset that is thesubject of a Reserve Asset Trigger Notice by delivering a written notice (the “ReserveAsset Option Notice”) stating Sumitomo’s intent to acquire an Interest inthe applicable Reserve Asset (an “Optioned Reserve Asset”).  The Reserve Asset Option Notice shall setforth the Reserve Asset in which Sumitomo elects to acquire an Interest and theamount of the Interest Sumitomo wishes to acquire, which in no case shall beless than 20% nor more than 35%, in each such case an Optioned Reserve Asset.

### (c)           Commencing upon receipt by Apex ofthe Reserve Asset Option Notice, Apex and Sumitomo shall (i) jointlydetermine a mutually acceptable structure for the acquisition of the Interestin the Optioned Reserve Asset, and (ii) enter into acquisition documentswith respect thereto that are on terms and conditions reasonably acceptable tothe Parties (including, among other documents, a shareholders or joint ventureagreement providing for the contribution by each party of its *pro rata* share of the future operating andcapital costs of the Optional Reserve Asset) (the “Reserve Definitive ExplorationProperty Agreements”).  The ReserveDefinitive Exploration Property Agreements shall include provisions for(A) rights of first refusal with respect to a Parties transfer of all orpart of their interest therein, (B) the contribution by each party of its *pro rata* share of future operating andcapital costs of the Optioned Reserve Assets, (C) if either Partyfails to contribute its proportionate share, the other Party shall have theright to contribute the non-contributing party’s share against theissuance of additional beneficial interests (in shares, quotas, membership orpartnership interest, or other comparable designation) to the contributingParty to reflect the adjusted proportionate holdings resulting from suchcontribution(s) (and non-contribution, as applicable), (D) at such time aParty’s beneficial interest in an Exploration Entity falls below 25% as aresult of clause (C) of this Section 4.3(c), such Party shall have nofurther rights with respect to the management of such Exploration Entity or theExploration Property it is developing except the right to have a director onthe Board of the Exploration Entity until the Party's beneficial interest inthe Exploration Entity falls below 20%, and (E) provisions, on such termsas the Parties may mutually agree, similar to ARTICLE II,Section 3.2, Section 3.3, Section 5.1 and Section 7.7 ofthe MSC Shareholders Agreement.  Apex shall cause any of itsSubsidiaries having rights in the applicable Optioned Reserve Asset to enterinto the Reserve Definitive Exploration Property Agreements to the extentreasonably required for Sumitomo to effectively acquire its Interest in theOptioned Reserve Asset.  Notwithstandingthe foregoing, Sumitomo may at any time prior to the execution of the ReserveDefinitive Exploration Property Agreement elect, by written notice to Apex, notto acquire an interest in one or more of the Optioned Reserve Assets to whichthe Reserve Definitive Exploration Property Agreement relates in which eventsuch Reserve Asset shall cease to be the subject to this Agreement.

## Section 4.4                Paymentfor Optioned Reserve Assets.  In consideration for each Optioned ReserveAsset, Sumitomo shall pay to Apex, at the closing of the acquisition of theInterest in such Optioned Reserve Asset, the Dollar amount in cash, equal tothe percentage

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## Interest of such Optioned Reserve Asset thatSumitomo is acquiring times the Optioned Asset Historical Costs with respect tosuch Optioned Reserve Asset that have been incurred up to the date ofSumitomo’s said payment.

## Section 4.5                Failure to Exercise ReserveAsset Option.  In theevent that Sumitomo elects not to exercise any Reserve Asset Option, or failsto timely deliver a Reserve Asset Option Notice, with respect to a ReserveAsset for which a Reserve Asset Option Notice has been delivered, thenSumitomo’s rights as set forth in this ARTICLE IV with respect to such ReserveAsset shall terminate and have no further force or effect, and, notwithstandinganything to the contrary in this Agreement, the Parties hereto shall have noliability, responsibility, or obligation, whatsoever, to each other in respectof this ARTICLE IV with respect to such Reserve Asset.

## Section 4.6                Cessation of a Reserve Asset;Third-Party Sale.  

### (a)           Except withrespect to an Optioned Reserve Asset or a Reserve Asset for which a ReserveAsset Trigger Notice has been delivered, if, during the Term, Apex either(i) makes a permanent election not to pursue development of a ReserveAsset or (ii) agrees (subject to this Agreement) to sell an interest in aReserve Asset to an unaffiliated third party (a “Reserve Third-PartySale”), then, promptly after such decision or agreement, Apex shall provideSumitomo written notice of same (the “Reserve Asset Cessation/Sale Notice”)together with the Asset Development Documents relating to such Reserve Asset,to the extent not already delivered. Sumitomo shall have the right to acquire all or part of the subjectReserve Asset on the terms and conditions set forth in Section 4.6(b) andSection 4.6(c).  

### (b)           If theReserve Asset Cessation/Sale Notice states that Apex has permanently electednot to pursue development of a Reserve Asset, then Apex shall indicate in theReserve Asset Cessation/Sale Notice the percentage interest of such ReserveAsset that Apex shall have the right to retain (the “Reserve RetainedInterest”); provided, however, that such Reserve RetainedInterest shall not exceed 35% of the interest in such Reserve Asset.  Sumitomo shall have 60 days from the date ofreceipt of the Reserve Asset Cessation/Sale Notice and the related AssetDevelopment Documents to elect to acquire the applicable Reserve Asset otherthan the Reserve Retained Interest therein on the terms, conditions, andprocedures set forth in Section 4.3(c). The purchase price for such interest shall be the Dollar amount, incash, equal to (i) the percentage interest of such Reserve Asset to beacquired by Sumitomo multiplied by (ii) the total amount of all OptionedAsset Historical Costs incurred by Apex for such Reserve Asset up tothe date of payment of such purchase price. 

### (c)           If the Reserve Asset Cessation/Sale Notice statesthat Apex intends to enter into a Reserve Third-Party Sale, then Apexshall indicate in the Reserve Asset Cessation/Sale Notice the terms and conditionson which such Reserve Asset is proposed to be sold to a third party (the “ReserveOffered Terms”) (including the percentage interest to be sold, sale price,and applicable time period in which the transaction shall

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### close). Sumitomo shall have 60 days from the date of receipt of the ReserveAsset Cessation/Sale Notice and the related Asset Development Documents toelect to acquire such interest in the applicable Reserve Asset on the ReserveOffered Terms.  Apex may sell suchReserve Asset to a third party on the Reserve Offered Terms within 120 days ofthe end of such 60-day period or within 120 days of Sumitomo’s failure toconsummate the transaction on the Reserve Offered Terms (including applicablerequired time periods with respect thereto) after having made an election to doso.  In the event Apex does not completesuch a sale to a third party on the Reserve Offered Terms, the Reserve Assetshall thereafter continue to be treated as a Reserve Asset subject to theprovisions of ARTICLE IV.

## Section 4.7                Access to Records.  During the Term of this Agreement, Apex shallafford to Sumitomo and its business, accounting, legal, engineering and otherrepresentatives, as well as their respective officers and employees, reasonableaccess, upon reasonable notice, to its documents, agreements, accountingrecords, and financial statements related to, and to the physical propertiescomprising, the Reserve Assets and shall permit Sumitomo and suchrepresentatives to make such tests, including soil and other field tests, ofsuch Active Assets as Sumitomo may reasonably request.

# **ARTICLE V****TERM AND TERMINATION**

## Section 5.1                Term.  

### (a)           Unlessotherwise agreed in writing by the Parties, the Parties obligations under thisAgreement shall commence on the Effective Date and shall terminate, along withthis Agreement, upon the date that is the earlier of (i) two years afterthe Effective Date, or (ii) the date on which the aggregate InterestRatios of the Sumitomo Interestholders in MSC is less than 20% (the “Term”).

### (b)           Subject toSection 5.2(a) and notwithstanding the foregoing, the Term shall be tolledsolely under the following circumstances:  (i) if the AssetDevelopment Documents related to any Active Asset have not been delivered to(or reviewed by) Sumitomo on or before the date that is 60 days prior to theend of the Term, or the Section 3.3 negotiation period with respect to suchActive Asset has not expired by the end of the Term, the Term shall be tolledwith respect to such Active Asset for the duration of the applicable ActiveAsset Option Term pursuant to Section 3.2 and any negotiation period withrespect thereto pursuant to Section 3.3(a); and (ii) if a Reserve AssetTrigger Notice has been delivered to or by Sumitomo with respect to a ReserveAsset, and the Asset Development Documents related to such Reserve Assethave not been delivered to (or reviewed by) Sumitomo on or before the date thatis 60 days prior to the end of the Term, or the Section 4.3 negotiation periodwith respect to such Reserve Asset has not expired by the end of the Term, theTerm shall be tolled with respect to such Reserve Asset for the duration of theapplicable Reserve Asset Option Term

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### pursuant toSection 4.2 and any negotiation period with respect thereto pursuant to Section4.3.

## Section 5.2                Effect of Termination.

### (a)           If(i) this Agreement is terminated pursuant to  Section 5.1(a)(i) and (ii) at such timeof termination, an Active Asset Option Notice or an Reserve Asset OptionNotice, as applicable, has been delivered to Apex, but the acquisition processset forth in ARTICLE III or ARTICLE IV, as applicable, has not been completedin accordance with the terms hereof, then, solely with respect to such optionedasset, this Agreement shall continue until consummation of the acquisition of suchasset.

### (b)           If(i) this Agreement is terminated pursuant to Section 5.1(a)(ii) and(ii) at such time of termination, an Active Asset Option Notice or an Reserve Asset Option Notice, asapplicable, has been delivered to Apex, but the acquisition process set forthin ARTICLE III or ARTICLE IV, as applicable, has not been completed inaccordance with the terms hereof, then this Agreement shall terminate andSumitomo shall have no further rights with respect to such asset.

# **ARTICLEVIFAILURE TO MAKE PAYMENT**

## Section 6.1                Failure to Make Holding CostPayment.  If Sumitomo fails to make  a Holding Costs Payment within 30 days of thedate (the “Payment Date”) such payment is due and payable, Sumitomoshall forfeit its interest and its rights to the Active Asset or Reserve Assetto which the Holding Costs Payment applies without further notice from Apex.

# **ARTICLE VII****ADDITIONAL PROVISIONS**

## Section 7.1                Entire Agreement.  This Agreement (together with the Purchaseand Sale Agreement and the other Transaction Documents) contain, and areintended as, a complete statement of all of the terms of the agreements amongthe Parties with respect to the matters provided for herein and therein, andsupersede and discharge any previous agreements and understandings between theParties with respect to those matters.

## Section 7.2                Confidentiality.  Each Party shall keep confidential, shallcause its Affiliates to keep confidential, and shall instruct its officers,directors, employees, and advisors to keep confidential, all information receivedfrom the other Party with respect to any Asset Development Document or ReviewDocument along with any due diligence investigation conducted relating to anActive Asset or Reserve Asset and the consummation of the transactionscontemplated by this Agreement or otherwise, except (i) as required byapplicable securities or other Laws or stock exchange rules or administrativeprocess, and (ii) for information that is or becomes generally availableto the public other than as a result of a breach of this Section 7.2 (suchinformation, subject to clauses (i) and (ii), “Confidential Information”).  Except to the

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## extent deemed necessary or advisable bycounsel to maintain compliance with, or to prevent violation of, applicablesecurities or other Laws or stock exchange rules, each Party shall keep theexistence of and the provisions of this Agreement and the other TransactionDocuments confidential and shall disclose their contents only (1) to thoselenders, investors, partners, shareholders, directors, officers, employees, andagents who need to know such information for purposes of its businesses and thetransactions contemplated hereby, and (2) to Governmental Authorities andthird parties for purposes of obtaining approvals for the transactions contemplatedhereby.  All Confidential Informationshall be treated as information covered by the Confidentiality Agreement, whichshall remain in full force and effect and shall not be modified or supersededin any way by this Agreement.  Withrespect to an Active Asset or Reserve Asset for which Sumitomo (or itsAffiliates) receives Asset Development Documents or Review Documents but doesnot acquire an Interest in such asset, Sumitomo (or its Affiliates)(i) shall promptly return to Apex all copies of such Asset DevelopmentDocuments or Review Documents in the possession or Sumitomo (or itsAffiliates), and, unless specifically prohibited by court order, Sumitomo (orits Affiliates) will destroy all copies of any analyses, compilations, studiesor other documents prepared by it or for its use containing or reflecting anysuch Asset Development Document or Review Document, and (ii) shall beprohibited from using any information in such Asset Development Document orReview Document for its (or its Affiliates) future benefit without the priorwritten consent of Apex.

## Section 7.3                Governing Law; Language.  This Agreement shall be governed by andconstrued in accordance with the Laws of the State of New York, includingSection 5-1401 of the New York General Obligations Law, as applied tocontracts made and performed within the State of New York, without regard toany choice or conflicts of law provision or rule that would cause theapplication of the Laws of any jurisdiction other than the State of New York.  This Agreement has been negotiated andexecuted by the Parties in English.  Inthe event any translation of this Agreement is prepared for convenience or anyother purpose, the provisions of the English version shall govern.  If any doubt, misunderstanding, or dispute arisesin their interpretation, the English version shall govern.

## Section 7.4                Dispute Resolution.  Any controversy,claim, or dispute between the Parties that arises out of or relates to thisAgreement, including any claim or controversy relating to payment obligationshereunder or the interpretation, breach, termination, or invalidity of anyprovision hereof, shall be exclusively and finally settled pursuant to and inaccordance with the Dispute Resolution Agreement.

## Section 7.5                Headings.  The article and section headings of thisAgreement are for reference purposes only and are to be given no effect in theconstruction or interpretation of this Agreement.

## Section 7.6                Notices.  All noticesand other communications hereunder shall be in writingand shall be deliveredpersonally, telecopied (if receipt of which is confirmed by the Person to whomsent), sent by internationally recognized overnight delivery service to theParties at the following addresses (or to such other Person or address for aParty as specified by such

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## Party by like notice) (notice shall be deemed given and receivedupon receipt, if delivered personally, by overnight delivery service or bytelecopy, except that notice of a change of address shall not be deemed given and received until actually received):

### (a)           Ifto Apex, to it at:

Apex Silver Mines Limitedc/o Apex Silver Mines Corporation1700 Lincoln Street, Suite 3050Denver, Colorado  80203 U.S.A.Attention:  Vice President of ExplorationTelecopier: +1 (303) 839-5907

### (b)           If to Sumitomo, to it at:

SumitomoCorporation8-11, Harumi, 1-chome,Chuo-ku, Tokyo, 104-8610 JapanAttention:  General Manager, Non-FerrousMetals                                & Raw Materials Dept.Telecopier:  +81-3-5166-6423

## Section 7.7                Severability.  If at any time any covenant or provision containedherein is deemed in a final ruling of a court or other body of competentjurisdiction (including an arbitral tribunal convened in accordance with theDispute Resolution Agreement) to be invalid or unenforceable, such covenant orprovision shall be considered divisible and such covenant or provision shall bedeemed immediately amended and reformed to include only such portion of suchcovenant or provision as such court or other body has held to be valid andenforceable (provided such amended and reformed provision shall be amended,reformed and construed in a manner that reflects and carries out the provisionsand the intent of the Parties); and the Parties agree that such covenant orprovision, as so amended and reformed, shall be valid and binding as though theinvalid or unenforceable portion had not been included herein. 

## Section 7.8                Amendment;Waiver.  Except as provided in Section 2.1(b), noprovision of this Agreement may be amended or modified except by an instrumentor instruments in writing signed by the Parties and designated as an amendmentor modification.  No waiver by any Partyof any provision of this Agreement shall be valid unless in writing and signedby the Party making such waiver and designated as a waiver.  No failure or delay by any Party inexercising any right, power, or remedy hereunder shall operate as a waiverthereof, nor shall any single or partial exercise thereof or the exercise ofany other right, power, or remedy preclude any further exercise thereof or theexercise of any other right, power, or remedy. No waiver of any provision hereof shall be construed as a waiver of anyother provision.

## Section 7.9                Assignmentand Binding Effect.  No Party may assign any of its rights ordelegate any of its obligations under this Agreement without (a) the priorwritten consent of the

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## other Party, and (b) the completewritten assumption by the assignee of all of the obligations of the assignorunder this Agreement.  All of the terms and provisions of thisAgreement shall be binding on, and shall inure to the benefit of, therespective successors and permitted assigns of the Parties.

## Section 7.10              No Benefit to Others.  Except as expressly set forth herein, therepresentations, warranties, covenants, and agreements contained in this Agreementare for the sole benefit of the Parties and their respective successors andpermitted assigns, and they shall not be construed as conferring and are notintended to confer any rights, remedies, obligations, or liabilities on anyother Person, unless such Person is expressly stated herein to be entitled toany such right, remedy, obligation, or liability. 

## Section 7.11              No Consequential Damages.  No Party shall be liablefor any punitive, multiple, or other exemplary damage or loss, or any indirect,special, incidental, or consequential loss or damage, lost profits, loss ofuse, or lost revenues suffered by any other Party arising from or relating to aParty’s performance, non-performance, breach of, or default under acovenant, warranty, representation, term, or condition of this Agreement.  Each Party waives and relinquishes claims forsuch punitive, multiple, exemplary, indirect, special, incidental, orconsequential losses or damages, lost profits, loss of use, or lostrevenues.  The limitations on liabilityand damages set forth in this Section 7.11 apply to all causes of action thatmay be asserted hereunder, whether sounding in breach of contract, breach ofwarranty, tort, product liability, negligence, or otherwise.

## Section 7.12              Counterparts.  This Agreement may be executed by the Partiesin separate counterparts, each of which when so executed and delivered shall bean original, but all such counterparts shall together constitute one and thesame instrument.

## Section 7.13              Interpretation.

### (a)           As used herein,except as otherwise indicated herein or as the context may otherwise require:(i) the words “include,” “includes,” and “including” are deemed to befollowed by “without limitation” whether or not they are in fact followed bysuch words or words of like import; (ii) the words “hereof,” “herein,”“hereunder,” and comparable terms refer to the entirety of this Agreement,including the Appendices hereto, and not to any particular article, section, orother subdivision hereof or Appendix hereto; (iii) any pronoun shallinclude the corresponding masculine, feminine, and neuter forms; (iv) thesingular includes the plural and vice versa; (v) references to anyagreement or other document are to such agreement or document as amended,modified, supplemented, and restated now or hereafter from time to time;(vi) references to any statute or regulation are to it as amended,modified, supplemented, and restated now or hereafter from time to time, and toany corresponding provisions of successor statutes or regulations;(vii) except as otherwise expressly provided in this Agreement, referencesto “Article,” “Section,” “preamble,” “recital,” or another subdivision or to an“Appendix” are to an article, section, preamble, recital or subdivision hereofor an “Appendix” hereto; and

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### (viii) referencesto any Person or Entity include such Person’s or Entity’s respective successorsand permitted assigns.

### (b)           Any reference herein to a “day” or number of “days”(without the explicit qualification of “Business”) shall be deemed to refer toa calendar day or number of calendar days. If any action or notice is to be taken or given on or by a particularcalendar day, and such calendar day is not a Business Day, then such action ornotice may be taken or given on the next succeeding Business Day.

### (c)           Any financialor accounting terms that are not otherwise defined herein shall have themeanings given thereto under GAAP.

## Section 7.14              Rulesof Construction.  The Parties agree that they have beenrepresented by counsel during the negotiation, preparation, and execution ofthis Agreement and, therefore, waive the application of any Law or rule ofconstruction providing that ambiguities in an agreement or other document shallbe construed against the Party drafting such agreement or document.

*[Remainderof page intentionally left blank]*

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IN WITNESSWHEREOF, the Parties have executed this Agreement as of the date first writtenabove.

 
|        | APEX SILVER MINES LIMITED |
|--------|---------------------------|
|   |                      |
|   | By:                       | /s/ Jeffrey Clevenger |   |
|   |                      | Jeffrey Clevenger |
|   | Its:                      | President & CEO |
|        |                           |  |  |  |

 

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|        | SUMITOMO CORPORATION |
|--------|----------------------|
|   |                 |
|   | By:                  | /s/ Mitsuhiko Yamada |   |
|   |                 | Mitsuhiko Yamada |
|   | Its:                 | Executive Officer and General Manager, |
|   |                 | Mineral Resources Division 1 |
|        |                      |  |  |  |

 

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