Exhibit 5.1

K&L Gates LLP

70 W. Madison St., Suite 3100

Chicago, IL 60602

312-372-1121

October 15, 2009

Hecla Mining Company

6500 North Mineral Drive, Suite 200

Coeur d’Alene, Idaho 83815

Ladies and Gentlemen:

We have acted as your counsel in connection with the Registration Statement on Form S-1 (the “Registration Statement”) filed with the Securities and Exchange Commission under the Securities Act of 1933 (the “1933 Act”) for the registration of 64,476 shares (the “Shares”) of common stock into which certain issued and outstanding shares of 12% Convertible Preferred Stock (the “Preferred Stock”) are convertible, of Hecla Mining Company, a Delaware corporation (the “Company”).

You have requested our opinion as to the matters set forth below in connection with the Registration Statement. For purposes of rendering that opinion, we have examined the Registration Statement, the Company’s Certificate of Incorporation, as amended, and Bylaws, and the corporate action of the Company that provides for the issuance of the Convertible Shares, and we have made such other investigation as we have deemed appropriate. We have examined and relied upon certificates of public officials and, as to certain matters of fact that are material to our opinion, we have also relied on a certificate of an officer of the Company. In rendering our opinion, we also have made the assumptions that are customary in opinion letters of this kind. We have not verified any of those assumptions.

Our opinion set forth below is limited to the Delaware General Corporation Law, including the applicable provisions of the Delaware Constitution and reported judicial decisions interpreting those laws.

Based upon and subject to the foregoing, it is our opinion that the Shares are duly authorized for issuance by the Company, and that the Shares, when issued and paid for in accordance with the conversion provisions of the Preferred Stock, will be validly issued, fully paid and nonassessable.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the reference to this firm in the related Prospectus under the caption “Legal Matters.” In giving our consent we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the 1933 Act or the rules and regulations thereunder.