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EARN-IN AGREEMENT AMENDMENT

This Earn-in Agreement Amendment
(EIA Amendment) is made as of February 28, 2006 between HECLA VENTURES CORP.,
a Nevada corporation duly qualified to do business and in good standing in the
state of Nevada, whose principal address is 6500 Mineral Drive, Coeur dAlene,
Idaho 83815-8788 (hereinafter referred to as Hecla Ventures) and its Guarantor
and parent company, Hecla Mining Company and RODEO CREEK GOLD INC., a Nevada
corporation whose address is c/o Richard Harris, Ste. 260-6121 Lakeside Drive,
Reno, NV 89511 (hereinafter referred to as Rodeo Creek) which is qualified to
do business and is in good standing in the State of Nevada and its Guarantor and
indirect parent company, Great Basin Gold Ltd.

RECITALS

A. WHEREAS the Parties entered
into an Earn-in Agreement effective August 2, 2002 (the Earn-In Agreement)
which the parties desire to amend hereby;

B. AND WHEREAS the Parties are
engaged in a legal dispute in connection with the Earn-in Agreement which this
EIA Amendment will resolve and settle;

NOW, THEREFORE, in consideration
of the payments provided for herein and the mutual promises set forth below, the
Parties hereby agree to the provisions of this EIA Amendment.

PART I

DEFINITIONS

1.1 Capitalized terms herein
shall have the meanings set forth in the Earn-in Agreement except as hereby
amended.

1.2 Feasibility Study the
existing definition in the Earn-in Agreement is hereby amended by adding to the
existing definition the following sentence: The Feasibility Study shall

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be either produced by, or endorsed by, an internationally recognized
  mining engineering firm which is independent of the parties.

1.3 Commercial Production
  the existing definition in the Earn-in Agreement is hereby deleted and replaced
  with the following: Commercial Production means the establishment
  of a mine on the Properties in the manner and at the production level recommended
  by the Feasibility Study and achievement of Commercial Production shall be deemed
  to occur upon the first operation of such mine at a minimum of 75% of the life
  of mine scheduled average production rate provided for in the Feasibility Study
  during any consecutive 30 day period.

PART II

TERM OF EARN-IN AGREEMENT

2.1 Article III of the Earn-in
Agreement is amended by substituting the following in its entirety:

ARTICLE III

TERM OF EARN-IN AGREEMENT

The Term of this Earn-in
Agreement shall commence as of the Effective Date and shall automatically
terminate on the earlier of (i) August 2, 2009 or (ii) the date that Hecla
Ventures vests in its 50% Interest pursuant to Article V, unless this Earn-in
Agreement is earlier terminated pursuant to Article VIII, or earlier terminated
pursuant to Article XIII on account of Hecla Ventures failing to meet the
requirements of Article V, or unless this Earn-in Agreement is extended by
amendment hereof upon the Parties mutual written agreement.

The parties hereby agree
deadlines included in this article shall be extended for a period of time equal
to the time that Hecla Ventures determines, acting reasonably, it is prohibited
from advancing or completing the requirements of this article (for example, lack
of legal access), by the action or inaction of Great Basin Gold, Rodeo Creek, or
any third party who holds an interest in or a contractual right effecting any
portion of the

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Properties. During any period in which Hecla Ventures
determines, acting reasonably, it is prohibited from advancing the activities
associated with Stage II and/or vesting by lack of legal access to any portion
of the Properties due to action or inaction of Great Basin Gold or Rodeo Creek
or any third party who holds an interest in or a contractual right effecting any
portion of the Properties, Rodeo Creek will pay 100% of the Projects holding
costs, as well as all costs during a 60-day remobilization period at the
recommencement of operations.

The language in the preceding
paragraph shall also apply to Hecla Ventures obligations under section 3.1
below, and any other provisions in the Earn-in Agreement. The provisions in
section 2.1 shall not restrict or preclude Hecla Ventures from exercising any
other rights or remedies provided for at law or under the Earn-in Agreement.

2.2 Section 8.4 of the Earn-in
Agreement is hereby deleted from the Agreement and Hecla agrees that completion
by it of the Attachment A activities is no longer optional but a commitment and
that material changes from Attachment A (which supersedes Exhibit E to the EIA)
will only be made with Rodeo Creeks consent.

PART III

INITIAL CONTRIBUTION AND REQUIRED EARN-IN
EXPENDITURES

3.1 Section 5.1(c) of the Earn-in
  Agreement is hereby deleted and substituted with the following:

“5.1 (c) Hecla Ventures hereby commits to complete and fund, at whatever
  cost, 100% of the remaining Stage I Earn-in Activities and to complete all such
  activities (except preparation and delivery of the Feasibility Study) by March
  31, 2007, failing which Rodeo Creek may, in addition to any other rights it
  may have, terminate Hecla Ventures’ Earn-in rights hereunder pursuant
  to Article XIII. Hecla Ventures also agrees that it is a condition to Hecla
  Ventures vesting in a 50% Participating Interest in the Properties that it achieves
  Commercial Production by

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August 2, 2009 failing which Hecla Ventures Earn-in rights under this
  Agreement may also be terminated by Rodeo Creek pursuant to Article XIII.

Each party will be obligated to fund its share of the Stage II Earn-in Activities.
  However, Hecla Ventures shall fund Rodeo Creeks portion of Stage II Expenditures
  towards achieving Commercial Production until the later of (i) 30 days after
  Hecla has delivered to Rodeo Creek the Feasibility Study and (ii) the date on
  which the amount Hecla Ventures Stage II Earn-in Expenditures, when aggregated
  with its Stage I Earn-in Expenditures, exceeds $21.8 million. Thereupon Rodeo
  Creek shall be obligated to pay its portion of Heclas Ventures Stage
  II Expenditures. In addition, no later than 120 days after Hecla has delivered
  to Rodeo Creek the Feasibility Study, Rodeo Creek will be obligated to repay
  Hecla Ventures for any and all Stage II expenditures that Hecla Ventures funded
  on behalf of Rodeo Creek. Hecla Ventures will send Rodeo Creek invoices for
  50% of Stage II costs following the submission of the Feasibility Study. If
  Rodeo Creek fails to remit full payment of the invoices within 30 days of the
  invoice date for their share of Stage II Expenditures, the failure to pay will
  be deemed a default in making a cash call and Hecla Ventures shall have all
  rights and remedies as provided in section 10.3 and 6.4 of Exhibit F to the
  Earn-In Agreement (the Joint Operating Agreement). In lieu of the rights and
  remedies provided in sections 10.3 and 6.4, Hecla Ventures shall have the right
  to elect to be repaid for any amounts due and in default from Rodeo Creek hereunder
  by retaining and marketing Rodeo Creeks first share of production under
  the Joint Operating Agreement until Hecla Ventures has received four times the
  amount of the default. In the event Rodeo Creek funds 100% of any Stage II activities
  and Hecla Ventures does not pay its portion, Rodeo Creek retains the same rights
  and remedies against Hecla Ventures as stated above. All expenditures incurred
  by Hecla Ventures in furtherance of Commercial Production, other than those
  expenditures specifically

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| | incurred in connection with the completion of the Stage I Earn-in
      Activities described in Attachment A, shall be deemed to be incurred for
      Stage II Earn-in Activities and they (plus the Feasibility Study) shall
      require the prior approval of the Management Committee as if Article VII
      of the Joint Operating Agreement were in effect and notwithstanding that
      Hecla Ventures has not yet vested and the Joint Operating Agreement is not
      otherwise effective. On approval of a Stage II development budget, and commencement
      of Stage II underground excavations or construction of Stage II infrastructure
      by Hecla Ventures, it shall, within ten (10) days thereafter, issue to Great
      Basin one million (1,000,000) Hecla Mining Warrants, (Tranche 2)
      in the form of the Warrant Agreement in Exhibit G exercisable at the Exercise
      Price and in accordance with the terms and conditions of the Warrant Agreement.
| | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

3.2 Sections 5.2, 5.4 and 5.5 of
the Earn-in Agreement are hereby deleted and substituted with the following:

| | 5.2 Reasonable Earn-in Activities. Hecla Ventures
      Stage I Earn-in Activities shall be conducted in accordance with Attachment
      A hereto. The Parties hereby approve the program and budget for Stage I
      Earn-in Activities
| | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|

| | 5.4 Completion of Required Earn-in Expenditures.
      Upon completion of Stage I Earn-in Activities, excluding preparation and
      delivery of the Feasibility Study, Hecla Ventures shall provide notice to
      Rodeo Creek that it (i) has completed Stage I Earn-in activities, (ii) intends
      to begin Stage II activities, and (iii) submits a proposed budget for Stage
      II activities. Together with the notice, Hecla Ventures shall provide to
      Rodeo Creek with a certification of expenses incurred during Stage I activities.
      Rodeo Creek may, at its own expense, commence an audit of Hecla Ventures
      Stage I expenditures by a licensed accounting firm. If Rodeo Creek chooses
      to audit Stage I expenditures, Hecla Ventures must be given
| | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|
|
|

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written notice of Rodeo Creeks
  intent to audit within 30 days of delivery of the Feasibility Study, and the
  audit engagement must commence within 45 days of delivery of the Feasibility
  Study. Unless such notice is received within 30 days, all expenditures for Stage
  I activities are deemed approved. Hecla Ventures shall provide a similar certification,
  and Rodeo Creek shall provide similar notices and abide by the same time frames
  upon the completion of Stage II Earn-in Activities. 
       5.5 Stage II Earn-in Activities and Transfer of
  Property. Hecla shall have earned a vested undivided Participating Interest
  in the Properties subject to the Joint Operating Agreement by (i) completing
  all Stage I Earn-in Activities (except the Feasibility Study) by March 31, 2007,
  
  (ii) delivering the Feasibility Study, 
  (iii) achieving Commercial Production by August 2, 2009, and (iv) issuing to
  Great Basin an additional one million (1,000,000) Hecla Mining Warrants (Tranche
  3) the date Commercial Production is achieved, in the form of the Warrant
  agreement in Exhibit G. The Tranche 3 warrants will be exercisable at the Exercise
  Price and in accordance with the terms and conditions of the Warrant Agreement
  and dated and priced on the date that Hecla gives notice under Section 5.4 to
  Rodeo Creek that Commercial Production has been achieved. Upon Hecla Ventures
  vesting:

(a) Rodeo Creek shall convey to Hecla Ventures an undivided fifty percent (50%)
of Rodeo Creeks interest in the Properties, by executing, acknowledging and
delivering to Hecla Ventures a good and sufficient conveyance in the form of
Exhibit C to this Earn-in Agreement;

(b) Rodeo Creek and Hecla Ventures shall cause to become effective the Joint
Operating Agreement in the form of the attached Exhibit F, which shall include
the Properties and shall have an effective date as of the date of the
above-described vesting; and

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(c) Rodeo Creek shall issue to Hecla Ventures the Great Basin Warrants
  set forth in Exhibit E and H.

PART IV

OPERATIONS AND GOVERNANCE

4.1 Section 9.1(a), Management
Committee  Organization and Composition, of the Earn-In Agreement, is
hereby amended by deleting the second sentence of Section 9.1(a) and
substituting the following:

The Management Committee shall consist
of two (2) members appointed by Rodeo Creek, one of whom shall be Mr. Walter
Segsworth or other person acceptable to Hecla, and two (2) members appointed by
Hecla Ventures, one of whom shall be Mr. Art Brown or other person acceptable to
Great Basin.

4.2 Section 9.5, Parameters
for Hecla Ventures Earn-in Activities, of the Earn-In Agreement is hereby
amended by deleting the last two sentences thereof and substituting the
following:

Except as otherwise provided in
section 5.1(c), proceeds from all Products (to a maximum of fifty thousand
(50,000) gold ounces or equivalent) produced from the Area of Interest during
the term of this Earn-in Agreement shall be distributed to Hecla Ventures and
Rodeo Creek as follows: (i) one hundred percent (100%) of ounces recovered in
connection with Stage I Earn-in Activities, to Hecla Ventures up to the
aggregate of Hecla Ventures actual costs of Stage I Earn-in Activities, not to
exceed $21.8 million plus fifteen percent (15%) and (ii) all other Stage I
ounces and all of the ounces recovered in connection with Stage II Earn-in
Activities, as to fifty percent (50%) to each of Hecla Ventures and Rodeo Creek.
All ounces produced after the first 50,000 ounces shall be distributed according
to the Participating Interests of the parties, subject to the Purchase Price
Royalty.

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PART V

SETTLEMENT OF LITIGATION AND MUTUAL RELEASES

5.1 On execution of this EIA
Amendment, Hecla Ventures and Hecla Mining shall dismiss with prejudice the
legal proceedings initiated by them against Rodeo Creek and Great Basin in
Nevada. By execution hereof, all the Parties agree that there are no longer any
outstanding claims or allegations of default or breaches of the Earn-In
Agreement, by or in respect of any of the Parties, and this EIA Amendment shall
constitute a mutual general release by each of the Parties of each other Party
from any action or claim arising to the date hereof in connection with the
Earn-In Agreement. Thereupon, the only rights and obligations existing between
the Parties are as contemplated by the Earn-In Agreement, as amended by this EIA
Amendment.

PART VI

CONFIRMATION OF OTHER EARN-IN AGREEMENT TERMS

6.1 In all other respects the
representations, warranties and covenants of the Parties contained in the
Earn-in Agreement and the terms and conditions therein provided are hereby
confirmed by the Parties to be in full force and effect, unamended.

IN WITNESS WHEREOF the Parties
have executed this EIA Amendment as of the date first above written.

|HECLA VENTURES CORP.                |                                     | RODEO CREEK GOLD INC.
|----------------------------------- | ----------------------------------- | ---------------------
|                                    |                                    
|                                    |                                    
|By: _______________________________ | By: _______________________________
|Authorized
      Signatory          | Authorized Signatory               
|                                    |                                    
|Phillips S.
      Baker, Jr.        | Ferdi Dippenaar                    
|Print Name                          | Print Name                         
|                                    |                                    
|Director                            |                                    
|Title                               | Title                              

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IN WITNESS WHEREOF the Guarantors
have executed this EIA Amendment as of the date first above written.

|HECLA MINING COMPANY          |                               | GREAT BASIN GOLD LTD.
|----------------------------- | ----------------------------- | ---------------------
|                              |                              
|By: _________________________ | By: _________________________
|Authorized
      Signatory    | Authorized Signatory         
|                              |                              
|Phillips S. Baker, Jr.        | Ferdi Dippenaar              
|Print Name                    | Print Name                   
|                              |                              
|President and CEO             | President and CEO            
|Title                         | Title                        

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ACKNOWLEDGEMENTS

|STATE OF IDAHO     | ) |   
|------------------ | - | --
|                   | ) | ss
|County of Kootenai | ) |   

|The foregoing
        instrument was acknowledged before me this _________ day of _________________________,
        2006, by Phillips S. Baker, Jr., Director of Hecla Ventures Corp., a Nevada
        corporation, on behalf of said corporation.
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | ______________________________________ 
      Notary Public in and for the State of Idaho
| | -----------------------------------------------------------------------------------------
| | Residing at: ___________________________                                                 
| | My Commission
      Expires: _________________                                           

|PROVINCE OF BRITISH | ) |   
|------------------- | - | --
|COLUMBIA            | ) | ss
|                    | ) |   
|County of Vancouver |   |   

|The foregoing instrument
      was acknowledged before me this _________ day of _________________________,
      2006, by _______________________, ____________________ of Rodeo Creek Gold
      Inc., a Nevada corporation, on behalf of said corporation.
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|

| | ____________________________________Notary Public in and
      for the Province of British
| | ------------------------------------------------------------------------------------------
| | Columbia                                                                                  
| | Residing at: ___________________________                                                  
| | My
      Commission Expires: _________________                                            

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ACKNOWLEDGEMENTS

|STATE OF IDAHO     | ) |   
|------------------ | - | --
|                   | ) | ss
|County of Kootenai | ) |   

|The foregoing
      instrument was acknowledged before me this _________ day of _________________________,
      2006, by Phillips S. Baker, Jr., President and Chief Executive Officer of
      Hecla Mining Company, a Delaware corporation, on behalf of said corporation.
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|
|                                                                                                                                                                                                                                                                             
|                                                                                                                                                                                                                                                                             
|                                                                                                                                                                                                                                                                             
|________________________________________                                                                                                                                                                                                                                     
|Notary Public in and for the State of Idaho                                                                                                                                                                                                                                  
|Residing at: _______________________________                                                                                                                                                                                                                                 
|My Commission Expires: _____________________                                                                                                                                                                                                                                 

|PROVINCE OF BRITISH | ) |   
|------------------- | - | --
|COLUMBIA            | ) | ss
|                    | ) |   
|County of Vancouver |   |   

|The foregoing
      instrument was acknowledged before me this _________ day of _________________________,
      2006, by _______________________, ____________________ of Great Basin Gold
      Ltd., a British Columbia corporation, on behalf of said corporation.
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|
|                                                                                                                                                                                                                                                                      
|                                                                                                                                                                                                                                                                      
|                                                                                                                                                                                                                                                                      
|_________________________________________                                                                                                                                                                                                                             
|Notary Public in and for the Province of British                                                                                                                                                                                                                      
|Columbia                                                                                                                                                                                                                                                              
|Residing at: ________________________________                                                                                                                                                                                                                         
|My Commission Expires:
      ______________________                                                                                                                                                                                                                   

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EXHIBIT A

Stage I Activities:

Listed below is a summary of the
Phase I activities that remain to be completed between January 2006 and March
31, 2007. Further detail of each of these activities is included in the program
and budget submitted to the Management committee in December 2005.

All physical work associated with
Phase I Exploration is scheduled to be completed before March 31, 2007. The
feasibility study document and the external review of the document may not be
completed by March 31, 2007.

|1. | Underground Exploration:Lateral
      development, I-drifting and underground diamond drilling are scheduled to
      be completed before March 31, 2007.
|-- | ---------------------------------------------------------------------------------------------------------------------------------------------------------

| | a. | Approximately 2,300 feet of Lateral Development
| | -- | -----------------------------------------------
| | b. | Approximately1,000 feet of I-drifting          
| | c. | Approximately 55,000 feet of diamond drilling  

| |  | i.   | Lateral Development:Includes provisions
        for grouting, ground support, and services.                                                                                                                                                         
| |  | ---- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| |  |      |                                                                                                                                                                                                                                                     
| |  | ii.  | I-Drifting:The crosscut and I-drifts
        will most likely be located on the west end of the Clementine vein, however
        this is subject to change once a part of the diamond drilling results
        are in hand.                         
| |  |      |                                                                                                                                                                                                                                                     
| |  | iii. | Diamond Drilling:The drills will
        collect 55,000 feet of drill core. The drilling contract has been awarded
        to Connors. Activities include assays, administration expenses, and accommodations
        for the contract core loggers.

|2. | Access Road:The access
        road will be maintained for the period of time that is required to complete
        the physical Phase I activities.                                                                                                                                                                   
|-- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|   |                                                                                                                                                                                                                                                                                                                       
|3. | Site Services:Hecla
        Ventures will maintain the existing infrastructure during the period that
        is required to complete the physical phase I activities.                                                                                                                                                
|   |                                                                                                                                                                                                                                                                                                                       
|   |                                                                                                                                                                                                                                                                                                                       
|   |                                                                                                                                                                                                                                                                                                                       
|   |                                                                                                                                                                                                                                                                                                                       
|   |                                                                                                                                                                                                                                                                                                                       
|4. | Equipment Leases:The
        fleet of mobile equipment, as well as some of the fixed plant equipment
        that has been purchased in a separate account and is being leased to the
        project, will be maintained for the period of time that is required to
        complete the physical Phase I activities.

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|5. | Environmental and Permitting:Hecla
      Ventures will maintain and comply with all existing permits for the period
      of time that is required to complete the physical Phase I
    activities.                                                                                                                                                                                   
|-- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|   |                                                                                                                                                                                                                                                                                                                                                                                       
|6. | Administration:Hecla Ventures will
      maintain reasonable employee levels necessary to complete the physical
      Phase I activities. Hecla Ventures will continue to pay property taxes,
      claim fees, appropriate insurance, office expenses, and vehicle expenses
      including transportation to the site until the completion of the physical
      Phase I activities.

Feasibility Study Activities

The following activities will be
completed to support preparation of a Feasibility Study Document of sufficient
quality to support financing of the project, if warranted. In general, those
activities are listed below.

|1. | Resource Estimate:A reserve and
      resource estimate will be prepared in accordance with SEC requirements and
      will be of a quality to support financing by the partners if the project
      is feasible.
|-- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|2. | Mine Planning and Engineering:                                                                                                                                                                      
|-- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|   |                                                                                                                                                                                                     
|   | a.                                                                                                                                                                                                  
|   | b.                                                                                                                                                                                                  
|   | c.                                                                                                                                                                                                  
|   | d.                                                                                                                                                                                                  
|   | e.                                                                                                                                                                                                  
|   |                                                                                                                                                                                                     
|3. | Processing:Investigate
        transportation and processing alternatives. Activities may include testing
        to support negotiation of a processing agreement with a custom processor.         
|   |                                                                                                                                                                                                     
|4. | Infrastructure:Engineer
        appropriate infrastructure, water handling, transportation requirements,
        water treatment, office facilities etc.                                            
|   |                                                                                                                                                                                                     
|5. | Permitting:Determine
        Phase II permitting requirements, which may include Environmental Assessment
        or EIS as well as updating of existing permits. Estimate new bonding requirements.
|   |                                                                                                                                                                                                     
|6. | Capital and Operating Cost Estimates:Complete an operating cost estimate to include mine operating costs,
        transportation costs, processing costs, administrative costs, etc.                
|   |                                                                                                                                                                                                     
|   | Complete a capital cost estimate to include
        development of a mine that will support commercial production as determined
        in the feasibility study.                                   

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