Exhibit 10.28        EXECUTION COPY

FOURTH AMENDMENT TO LOAN AGREEMENT

THIS FOURTH AMENDMENT TO LOAN AGREEMENT (this "Fourth Amendment") is made and entered
into as of December 17, 2008, by and between SC MINERALS AKTIEBOLAG, a privat aktiebolag organized under the laws of Sweden (the "Lender") and
MINERA SAN CRISTÓBAL, S.A., asociedad anónimaorganized under the laws of Bolivia (the
"Borrower"). The Lender and the Borrower are referred to herein collectively as the "Parties" and
individually as the "Party".

BACKGROUND

WHEREAS,
the Borrower and the Lender are Parties to that certain Loan Agreement, dated as of August 11, 2008, as amended by that certain First Amendment
to Loan
Agreement dated October 1, 2008, that certain Second Amendment to Loan Agreement dated October 31, 2008, and that certain Third Amendment to Loan Agreement dated November 25, 2008
(as it may be further amended, modified, supplemented or amended and restated from time to time, the "Agreement");

WHEREAS,
the Lender has agreed, subject to the terms and conditions of the Agreement and this Fourth Amendment, to increase the amount of additional loans available to the Borrower by
US$25,000,000, up to a maximum aggregate principal amount of US$100,000,000 (the "Additional Loan"), upon the terms and conditions set forth therein and
herein;

WHEREAS,
the Borrower and Lender wish to further amend the Agreement as herein provided;

NOW,
THEREFORE, in consideration of the agreements and provisions herein contained, the parties hereto do hereby agree as follows:

1.Definitions.Any capitalized terms used but not otherwise defined herein shall have the meanings ascribed to
such terms in the Common Security Agreement, the Borrower Shareholders Agreement or the Agreement, as the case may be.

2.Amendments to Agreement.The Agreement is hereby amended, effective as of the date that this Fourth Amendment
becomes effective in accordance withSection 4hereof, as follows:



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3.Borrower Representations and Warranties.In order to induce Lender to enter into this Fourth Amendment,
Borrower hereby represents and warrants that:



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4.Conditions.This Fourth Amendment shall be effective as of December 17, 2008 (the
"Effective Date") upon the fulfillment by Borrower, in a manner satisfactory to Lender, of all of the following conditions precedent set forth in
thisSection 4:



5.Covenants.



6.Miscellaneous.



7.Other Provisions.



[Signatures Follow.]

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IN WITNESS WHEREOF, the undersigned parties have executed this Fourth Amendment as of the date first written above.

MINERA SAN CRISTÓBAL, S.A.By:

/s/ Jeffrey G. ClevengerName:

Jeffrey G. ClevengerTitle:

Director


|                          |  |      
|------------------------- |  | -----
|STATE OF COLORADO         |  | )    
|                          |  | ) ss.
|CITY AND COUNTY OF DENVER |  | )    

On
this            day of                    2008, personally appeared before me, a Notary
Public, Jeffrey G. Clevenger, personally known or proved to me to be the person whose name is
subscribed to the above instrument who acknowledged to me that he executed the above instrument.

Witness
my hand and official seal.

Notary Public


My
commission expires:

(TO
BE APOSTILLED)

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SC MINERALS AKTIEBOLAGBy:

/s/ Akira TakeuchiName:Title:


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In
consideration of the direct and indirect benefits that Apex Sweden and Apex Luxembourg will receive as Shareholders of the Borrower from the making of the Additional Loan, and as an
express condition to the making of the Additional Loan by the Lender, by their signature below Apex Sweden and Apex Luxembourg (i) consent to the making of the Additional Loan by the Lender in
accordance with the terms of the Agreement as amended by this Fourth Amendment, (ii) agree to comply with and be bound by the terms and provisions of the Agreement as amended by this Fourth
Amendment, including, without limitation,Section 1.8andArticle 4, (iii) agree
that any Shareholder Loan, Supplemental Loan or Consolidated Loan made by the Apex Interestholders and any other amount payable to the Shareholders by the Borrower, whether currently outstanding or
hereafter created, shall rank in payment and upon liquidation junior to the Additional Loan in accordance with the subordination terms attached to the Agreement as amended by this Fourth Amendment.

APEX SILVER MINES SWEDEN AB.By:

/s/ Gerald J. MalysName:

Gerald J. MalysTitle:

Deputy DirectorAPEX LUXEMBOURG S.À. R.L.By:

/s/ Gerald J. MalysName:

Gerald J. MalysTitle:

Manager


|                          |  |      
|------------------------- |  | -----
|STATE OF COLORADO         |  | )    
|                          |  | ) ss.
|CITY AND COUNTY OF DENVER |  | )    

On
this            day of                    2008, personally appeared before me, a Notary
Public, Gerald J. Malys, personally known or proved to me to be the person whose name is
subscribed to the above instrument who acknowledged to me that he executed the above instrument.

Witness
my hand and official seal.

Notary Public


My
commission expires:

(TO
BE APOSTILLED)

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