FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

Exhibit 10.5

FOURTH AMENDMENT TO

AMENDED AND RESTATED CREDIT AGREEMENT

THIS FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (this “ Fourth Amendment ”), dated as of February 3, 2009, is by and among HECLA MINING COMPANY, a Delaware corporation (the “ Borrower ”) and each of the banks and other financial institutions identified as Lenders on the signature pages hereto (the “ Lenders ”).

W I T N E S S E T H:

WHEREAS, pursuant to the Amended and Restated Credit Agreement, dated as of April 16, 2008 (as amended, supplemented or otherwise modified prior to the date hereof, the “ Existing Credit Agreement ” and, as amended by this Fourth Amendment and as the same may be further amended, supplemented or otherwise modified from time to time, the “ Credit Agreement ”), among the Borrower, the Lenders party thereto, and The Bank of Nova Scotia, as administrative agent for the Lenders (in such capacity, the “ Administrative Agent ”), the Lenders have made commitments to extend certain credit facilities to the Borrower; and

WHEREAS, the Borrower has requested that the Lenders agree to amend certain provisions of the Existing Credit Agreement as more specifically set forth herein, in each case upon the terms and conditions contained in this Fourth Amendment;

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, and in consideration of the agreements herein contained, the parties hereby agree as follows:

PART I

DEFINITIONS

SUBPART 1.1 Certain Definitions . Unless otherwise defined herein or the context otherwise requires, the following terms used in this Fourth Amendment, including its preamble and recitals, have the following meanings:

“ Administrative Agent ” is defined in the recitals .

“ Borrower ” is defined in the preamble .

“ Credit Agreement ” is defined in the recitals .

“ Existing Credit Agreement ” is defined in the recitals .

“ Lenders ” is defined in the preamble .

“ Fourth Amendment Effective Date ” is defined in Subpart 4.1 .

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SUBPART 1.2 Other Definitions . Unless otherwise defined herein or the context otherwise requires, terms used in this Third Amendment, including its preamble and recitals, have the meanings provided in the Credit Agreement.

PART II

AMENDMENTS TO EXISTING CREDIT AGREEMENT

Effective on (and subject to the occurrence of) the Fourth Amendment Effective Date, the Existing Credit Agreement is hereby amended in accordance with this Part II . Except as so amended, the Existing Credit Agreement and the other Loan Documents shall continue in full force and effect.

SUBPART 2.1 Amendment to Section 1.1 . Section 1.1 of the Existing Credit Agreement is hereby amended as follows:

(a) by inserting the following defined terms in the appropriate alphabetical sequence:

“ 2009 Budget ” means the Borrower’s 2009 Budget & Long Range Plan, dated January 26, 2009, as delivered to the Administrative Agent and the Lenders on January 30, 2009.

“ Accumulated Asset Sale Liquidity Amount ” means, as of any date, an amount equal to 50% of the Retained Net Disposition Proceeds received in respect of any Dispositions occurring from date hereof to such date.

“ Convertible Preferred Stock ” means the Borrower’s 12% Convertible Preferred Stock with the terms set forth in the form of certificate of designations attached as Exhibit A to the Fourth Amendment.

“ Exploration Costs ” means, for any period, the aggregate amount of any expenditure of the Borrower or any Subsidiaries in respect of exploration, evaluation and possible development and mining of mineral resources (including, without limitation, (i) expenditures relating to activities carried out (a) in search of previously unidentified mineral deposits, (b) at undeveloped concessions, or (c) at operating mines already containing proven and probable reserves, where a determination remains pending whether new target deposits outside of the existing reserve areas can be economically developed), and (ii) all expenses classified (or required to be classified, pursuant to the Borrower’s accounting policies) as “Other operating expenses—Exploration” on the Borrower’s consolidated statements of operations and comprehensive income (loss).

“ Fourth Amendment ” means the Fourth Amendment to Credit Agreement, dated as of February 3, 2009, among the Borrower, the Administrative Agent and the Lenders party thereto.

“ Fourth Amendment Effective Date ” has the meaning set forth in the Fourth Amendment.

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“ September Additional Amount ” means 25% of the amount by which the Net Equity/Subordinated Debt Proceeds referred to in Subpart 4.8 of the Fourth Amendment exceed $50,000,000.00; provided that, in no event shall the September Additional Amount exceed $2,500,000.00.

“ Series 2 Warrants ” means the Borrower’s Series 2 Common Stock Purchase Warrants.

(b) by amending and restating the following defined terms in their entirety to read as follows:

“ Excess Cash Flow ” means, for any period, the excess (if any), of

(x) EBITDA for such period;

minus

(y) the sum (for such period) of (A) Interest Expense actually paid in cash by the Borrower and Subsidiaries, plus (B) principal repayments, to the extent actually made, of Loans pursuant to clauses (a)  or (b)  of Section 3.1.1 or upon the Stated Maturity Date of such Loans ( excluding , however , repayments made from a refinancing of any portion of such Indebtedness, or pursuant to any other clause of Section 3.1.1 (including on the Stated Maturity Date thereof)) plus (C) all income Taxes actually paid in cash by the Borrower and Subsidiaries plus (D) Capital Expenditures made in cash ( excluding , however , Capital Expenditures financed with the proceeds of Indebtedness, equity issuances, casualty proceeds or other proceeds which are not included in EBITDA) plus (E) reclamation expenses actually paid in cash by the Borrower and its Subsidiaries ( excluding , however , reclamation expenses financed with the proceeds of insurance).

“ Required Lenders ” means, at any time, Lenders (a) holding more than 66 2/3% of the Total Exposure Amount and (b) comprising more than 50% of the total number of Lenders.

“ Retained Net Disposition Proceeds ” means, (a) the Net Disposition Proceeds from the sale of the Velardena Mill, and (b) with respect to any other Disposition by the Borrower or any Subsidiary pursuant to clause (e) of Section 7.2.10 , the amount of Net Disposition Proceeds in respect of such Disposition, net of any such Net Disposition Proceeds required to be used to repay the Loans pursuant to Section 3.1.1(d).

“ Retained Proceeds ” means, with respect to any date of determination, an amount (which may be a negative amount) equal (without duplication) to:

(a) the aggregate cumulative sum of (a) 65% of Excess Cash Flow for the 2008 Fiscal Year and (b) with respect to all periods after the 2008 Fiscal Year: (i) 25% of the Excess Cash Flow for the period commencing with the first day of the

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applicable Fiscal Year to and including the last day of the second Fiscal Quarter of such Fiscal Year and (c) 25% of the Excess Cash Flow for the period commencing with the first day of the third Fiscal Quarter of the applicable Fiscal Year to and including the last day of such Fiscal Year; provided that all applicable repayments under clause (e)  of Section 3.1.1 for such Fiscal Year or the applicable two-Fiscal Quarter period, as applicable, have been made;

plus

(b) with respect to any Investment permitted under clause (d)  (other than with respect to the Greens Creek Mine, the Lucky Friday Mine, the Isidora Mine or the La Comorra Mine), (e)(i) , (f)(i) , (h) , (i) , (j)  and (l)  of Section 7.2.5 , 25% of the aggregate amount of Net Equity/Subordinated Debt Proceeds received in connection with the issuance or sale of Capital Securities (excluding, for the avoidance of doubt, any Net Equity/Subordinated Debt Proceeds received in connection with exercise of the Series 2 Warrants) for the purpose of financing such Investment; provided that all applicable repayments under clause (c)  of Section 3.1.1 for such Fiscal Year have been made;

minus

(c) the aggregate of any amounts set forth in clauses (a)  and (b)  above previously applied to the making of any Investment permitted under clause (d)  (other than with respect to the Greens Creek Mine, the Lucky Friday Mine, the Isidora Mine or the La Comorra Mine), (e)(i) , (f)(i) , (h) , (i) , (j)  and (l)  of Section 7.2.5 .

“ Velardena Mill ” means the gold an silver recovery cyanide plant located near the town of Velardena in Durango State, Mexico which is currently held by Minera Hecla SA de CV, including (i) rights such as water and land use rights, (ii) permits such as operating and environmental permits, and (iii) infrastructure and equipment.

SUBPART 2.2 Amendment to Section 3.1.1 .

(a) Clause (b) of Section 3.1.1 of the Existing Credit Agreement is hereby amended in its entirety to read as follows:

(b) (i) On the Quarterly Payment Date set forth below, the Borrower shall make repayments of the outstanding principal amount of the Term I Loans in the amount set forth below opposite such period as follows:

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(b) Clause (c) of Section 3.1.1 of the Existing Credit Agreement is hereby amended and restated as follows:

(c) Concurrently with the receipt by the Borrower of any Net Equity/Subordinated Debt Proceeds in respect of the exercise of Series 2 Warrants, the Borrower shall make a mandatory prepayment of the Term I Loans in an amount equal to 100% of such Net Equity/Subordinated Debt Proceeds. Concurrently with the receipt by the Borrower of any other Net Equity/Subordinated Debt Proceeds (other than the proceeds described in Subpart 4.8 of the Fourth Amendment), the Borrower shall make a mandatory prepayment of the Term I Loans in an amount equal to 75% of such Net Equity/Subordinated Debt Proceeds.

(c) Clause (d) of Section 3.1.1 of the Existing Credit Agreement is hereby amended by adding the following text at the end thereof:

Notwithstanding the foregoing, upon written notice by the Borrower to the Administrative Agent not more than five Business Days following receipt of Net Disposition Proceeds from the sale of the Velardena Mill, such proceeds may be retained by the Borrower and its Subsidiaries (and be excluded from the prepayment requirements of this clause), if (y) the Borrower informs the Administrative Agent in such notice of its good faith intention to apply such Net Disposition Proceeds to funding Capital Expenditures in accordance with the 2009 Budget and (z) within 365 days following the receipt of such Net Disposition Proceeds, such proceeds are actually applied to Capital Expenditures in accordance with the 2009 Budget.

(d) Clause (e) of Section 3.1.1 of the Existing Credit Agreement is hereby amended and restated as follows:

(e) Within 100 days after the close of the second Fiscal Quarter of each Fiscal Year, the Borrower shall make a mandatory prepayment of the Term I Loans in an amount equal to 75% of Excess Cash Flow (if any) for the period from the first day of such Fiscal Year to and including the last day of the second Fiscal Quarter of such Fiscal Year, and within 100 days after the last day of each Fiscal Year, the Borrower shall make a mandatory prepayment of the Term I Loans in an amount equal to 75% of Excess Cash Flow (if any) for the period from the first day of the third Fiscal Quarter of such Fiscal Year to and including the last day of such Fiscal Year.

(e) Clause (f) of Section 3.1.1 shall be amended by adding the following text in place of the period at the end thereof:

; provided that , the Borrower shall not be required to make any mandatory prepayment with such released cash or cash equivalents to the extent that such released cash or cash equivalents represent accrued interest on the cash or cash equivalents that are the subject of the Liens described in clauses (c)  and (g)(ii) of Section 7.2.3 .

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SUBPART 2.3 Amendment to Section 3.3 . Section 3.3 of the Existing Credit Agreement is hereby amended by adding the following clause at the end thereof:

SECTION 3.3.3 Additional Fee . Upon the Fourth Amendment Effective Date, and on each July 1 and January 1 occurring thereafter, the Borrower shall issue to the Lenders, or, with respect to any Lender, to an institution designated by such Lender that at the time of issuance is an accredited investor under Regulation D under the Securities Act of 1933 and that agrees to hold the shares for its own account and not with a view towards distribution (on a pro rata basis according to each such Lender’s Term I Percentage) an amount of shares of a new series of Convertible Preferred Stock such that the aggregate liquidation preference of such shares equals the product of 3.75% and the aggregate principal amount of Term I Loans then outstanding. Any fractional shares resulting from the foregoing calculation shall be rounded up to the nearest whole share.

SUBPART 2.4 Amendments to Section 7.1 .

(a) Clause (u) of Section 7.1.1 of the Existing Credit Agreement is hereby amended and restated as follows:

(u) as soon as possible, on or before the Wednesday of each week following the Fourth Amendment Effective Date, an actual-to-forecast variance analysis for the preceding week and on a cumulative basis based upon a weekly rolling cash flow forecast for the thirteen week period which shall detail all sources and uses of cash on a weekly basis. Such thirteen week rolling cash forecast shall be updated and provided to the Administrative Agent on the first Monday of each month, together with an explanation of any changes between the updated forecast and the immediately preceding forecast, and shall include a summary of the general assumptions in such forecast (including relating to metals pricing and production volumes), in each case prepared and certified by the chief financial or accounting Authorized Officer of the Borrower, in form and detail satisfactory to the Administrative Agent;

(b) Clause (x) of Section 7.1.1 of the Existing Credit Agreement is hereby amended and restated as follows:

(x) beginning on the Fourth Amendment Effective Date, on a monthly basis (or more frequently as requested by the Administrative Agent), the Borrower shall, and shall cause the CRO, to host and participate in status and update calls with the Lenders to discuss, among other things, the current financial condition of the Borrower and its Subsidiaries and other topics reasonably requested by the Administrative Agent; and

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(c) Section 7.1.1 of the Existing Credit Agreement is hereby amended by inserting the following clause at the end thereof:

(z) (i) between July 1, 2009 and July 15, 2009 an updated budget and long range plan for the 2009 Fiscal Year, in form substantially similar to the 2009 Budget, and (ii) within 30 days after the start of each Fiscal Year thereafter, an updated budget and long range plan for such Fiscal Year, in form substantially similar to the 2009 Budget.

(d) Section 7.1 of the Existing Credit Agreement is hereby amended by inserting the following at the end thereof:

SECTION 7.1.17 Sale Price of Gold, Silver, Lead and Zinc . The Borrower and its Subsidiaries shall sell all gold, silver, lead and zinc on fair and reasonable terms, at prices and other terms no less favorable to the Borrower or such Subsidiary than it could obtain in an arm’s-length transaction with Person that is not an Affiliate.

SECTION 7.1.18 Convertible Preferred Stock . The Borrower shall at all times reserve a number of shares of Convertible Preferred Stock equal to or greater than the number of shares of Convertible Preferred Stock that it could be required to issue to the Lenders through the Stated Maturity Date pursuant to Section 3.3.3 hereof.

SUBPART 2.5 Amendments to Section 7.2 .

(a) Section 7.2.4 of the Existing Credit Agreement is hereby amended and restated as follows:

Section 7.2.4 Financial Condition and Operations .

The Borrower will not permit any of the events set forth below to occur:

(a) EBITDA computed for the period beginning January 1, 2009 through the end of the Fiscal Quarter ending on the date set forth below to be less than the corresponding amount of EBITDA set forth below:

(b) EBITDA computed for the four Fiscal Quarter period consisting of the Fiscal Quarter ending on the date set forth below and each of the three immediately preceding Fiscal Quarters to be less than the corresponding amount of EBITDA set forth below:

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(c) Capital Expenditures during the period beginning January 1, 2009 through the end of the Fiscal Quarter ending on the date set forth below to exceed the correspon