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                  FIRST SUPPLEMENTAL INDENTURE

     FIRST SUPPLEMENTAL INDENTURE dated and effective as of December 31, 
1997, by and between Royal Oak Mines Inc., a corporation amalgamated under 
the laws of Ontario, Canada (the "Company") and Chase Manhattan Trust 
Company, National Association, the successor to Mellon Bank, F.S.B., as 
Trustee (the "Trustee").

     Royal Oak Mines Inc. issued an aggregate principal amount of 
$175,000,000 of 11% Senior Subordinated Notes due 2006 and Series B 11% 
Senior Subordinated Notes due 2006 (collectively, "the Notes") pursuant to an 
Indenture dated as of August 12, 1996 (the "Indenture") by and among Royal 
Oak Mines Inc., the Trustee and Kemess Mines Inc. ("Kemess"). Kemess was a 
Guarantor as defined in and for purposes of the Indenture. On December 29, 
1997, Royal Oak Mines Inc. and Kemess amalgamated under the laws of Ontario, 
Canada and the surviving entity of such amalgamation is the Company. Section 
9.02 of the Indenture provides that the Indenture may be amended or 
supplemented by the Company and the Trustee when authorized by a resolution 
of the board of directors of the Company and consented to in writing by the 
holders of at least a majority in aggregate principal amount of the 
outstanding Notes. The Company has designated a record date of November 30, 
1997 for the purpose of obtaining such written consent and, as of the date 
hereof, the holders of a majority in aggregate principal amount of the Notes 
have provided their written consent to the amendments and supplements 
contained in this First Supplemental Indenture.

     Each party hereto agrees as follows for the benefit of the other party 
and for the equal and rateable benefit of the Holders of the Notes.

1.  Section 1.01 is hereby amended by deleting in its entirety the definition 
    of "Working Capital Facility" contained in that section and by inserting 
    in alphabetical order in section 1.01 the following definition:

         "Senior Secured Debentures" means, collectively, (i) the Senior 
         Secured Debenture dated December 31, 1997 issued by the Company to 
         and in favour of DDJ Canadian High Yield Fund in the principal amount
         of Cdn. $19,500,000, (ii) the Senior Secured Debenture dated December
         31, 1997 issued by the Company to and in favour of Goldman, Sachs &
         Co. in the principal amount of $16,100,000, and (iii) the Senior
         Secured Debenture dated December 31, 1997 issued by the Company to 
         and in favour of Mellon Bank, N.A., solely in its capacity as
         Trustee for General Motors Employees Domestic Group Pension Trust,
         in the principal amount of $14,600,000; as any or all of such 
         Senior Secured Debentures may be amended, modified, supplemented,
         restated, or assigned from time to time."

2.  Clauses (iv) and (vi) of the definition of "Permitted Indebtedness" 
    contained in section 4.12 of the Indenture are hereby deleted in their
    entirety and replaced, respectively, with the following:

         "(iv) Indebtedness under or in relation to the Senior Secured 
         Debentures in aggregate principal amounts not to exceed the
         aggregate of Cdn. $19,500,000 and U.S. $30,700,000, together with
         all interest, fees, and other amounts payable under or in respect
         of the Senior Secured Debentures;" and

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         "(vi) additional Indebtedness of the Company if, and to the extent
         that, the principal amount of the Senior Secured Debentures is repaid
         so that, to the extent the Company repays obligations under the 
         Senior Secured Debentures, in whole or in part, the Company may Incur
         additional Indebtedness under this clause in aggregate principal 
         amounts which, as of the date of Incurrence, when added to the 
         principal amounts of Senior Secured Debentures then outstanding (if 
         any) do not exceed the aggregate of Cdn. $19,500,000 and U.S. 
         $30,700,000;".

3.  Clauses (i) and (ii) of the definition of "Permitted Liens" contained in 
    section 1.01 of the Indenture are hereby deleted in their entirety and
    replaced, respectively, with the following:

         "(i) Liens on the assets or property of the Company or of a 
         Restricted Subsidiary that, in each case, secure Indebtedness 
         permitted under paragraph (b) of section 4.12 or clause (vi) of
         the definition of Permitted Indebtedness contained in section
         4.12;" and

         "(ii) Liens on the assets or property of the Company or of a 
         Restricted Subsidiary that, in each case, secure Indebtedness 
         permitted under clause (iv) of the definition of Permitted 
         Indebtedness contained in section 4.12;".

4.  Acknowledgement is hereby made of the amalgamation of the former Royal 
    Oak Mines Inc. and Kemess Mines Inc. on December 29, 1997 under the laws
    of the Province of Ontario, Canada in accordance with section 5.01 of the
    Indenture and resulting in the surviving entity being the Company. The 
    Indenture is hereby amended and supplemented in every respect to the 
    extent necessary to give effect to such amalgamation and conform the 
    Indenture thereto and to give effect to all sections of this First 
    Supplemental Indenture and conform the Indenture thereto.

5.  This First Supplemental Indenture is entered into, and the amendments and
    supplements contained herein are made, pursuant to the provisions of 
    section 9.02 of the Indenture.

     IN WITNESS WHEREOF, the parties hereto have caused this First 
Supplemental Indenture to be duly executed and effective, all as of the date 
first written above.

                                      ROYAL OAK MINES INC.

                                      by: /s/ James H. Wood
                                         -------------------------------------
                                         Name:  James H. Wood
                                         Title: Chief Financial Officer


                                      CHASE MANHATTAN TRUST COMPANY,
                                      NATIONAL ASSOCIATION, as Trustee

                                      by:
                                         -------------------------------------
                                         Name:
                                         Title: