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                                                                  EXHIBIT 10.4




          AMENDING AGREEMENT of a NET SMELTER RETURN ROYALTY dated as of the
      30th day of June, 2001,

BETWEEN:


          MESTON RESOURCES INC.
          (the "Owner")


          - and-

          REPADRE CAPITAL CORPORATION
          (the "Payee")

WITNESSES THAT:

          WHEREAS the Owner and the Payee entered into a Net Smelter Return
Royalty dated April 23rd, 1993 (the "Royalty Agreement") whereby the Payee has
agreed to purchase a net smelter return royalty on the mineral production from
property comprised of a mining concession and certain mining claims near
Chibougamau, Quebec owned by the Owner, which property is known as the "Joe
Mann Property" (the "Property");

          WHEREAS the Payee and Campbell Resources Inc. ("Campbell"), the sole
shareholder of the Owner, entered into a letter agreement dated April 30,
2001, pursuant to which, as part of a proposed merger by way of Plan of
Arrangement as described in a Joint Management Proxy Circular dated May 10,
2001 (the "Merger"), Campbell agreed to issue 800,000 common shares to the
Payee in consideration of the Payee agreeing to a reduced Net Smelter Return
Royalty as set out below;

          AND WHEREAS the Merger was approved by shareholders of Campbell and
was effective on June 30, 2001 and the Owner and the Payee wish to reflect the
above reduction in a formal amendment to the Royalty Agreement,

          NOW THEREFORE in consideration of the mutual covenants and
agreements herein contained and for other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged by each of the parties
hereto, it is agreed as follows:

          1.   The Payee hereto agrees that in consideration of the issuance
               and delivery to the Payee of 800,000 freely tradeable common
               shares of Campbell, the adequacy of which is agreed to and
               acknowledged by the Parties, the net smelter return royalty
               will be amended and reduced as set out in Section 2 hereof.



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          2.   The Owner and the Payee agree to amend subsections 9(a) and
               9(d) of the Royalty Agreement to read as follows:

                      9 (a) Precious Metals

                            The Owner shall pay to the Payee, a Royalty equal
                      to the following percentages of Net Smelter Returns (as
                      defined in subsection 9 (b) hereof) from the sale or
                      other disposition of gold mined or otherwise recovered
                      from the Property:

                            (i)     1.5% when the price of gold is US$325 per
                                    ounce or above. The royalty rate will
                                    increase by 1 basis point for every
                                    US$1.00 increase in the gold price above
                                    US$325 per ounce to a maximum of 2.0% at a
                                    gold price of US$375 per ounce or greater;

                            (ii)    Once Cdn$500,000 has been received in
                                    royalty payments under Section 9(a)(i)
                                    above the royalty rate will reduce to a
                                    flat 1% rate and will only be in effect at
                                    a gold price of US$350 per ounce or
                                    higher;

                      The price of gold is the price used in determining the
                      Royalty payment in subsection 9 (d) as herein amended.

                      The Owner shall further pay to the Payee a Royalty equal
                      to 2% of the Net Smelter Returns from the sale or other
                      disposition of silver mined or otherwise recovered from
                      the Property, on the silver production from the Property
                      in excess of one million ounces per calendar year.

                      The Owner shall further pay to the Payee a Royalty equal
                      to 2% of the Net Smelter Returns from the sale or other
                      disposition of copper mined or otherwise recovered from
                      the Property, on the copper production from the Property
                      in excess of five million pounds per calendar year.

          3.   The Owner and the Payee agree to amend subsection 9(d) of the
               Royalty Agreement as follows, to remove the reference to
               conversion of the gold price from US to Canadian dollars:

                      9 (d) Payment Time and Manner - Royalty on Gold

                      The Royalty on gold shall be calculated and paid monthly
                      on a calendar month basis commencing on May 1, 1993 by
                      the Owner regardless of arrangements the Owner shall
                      have made for smelting and refining and regardless of
                      the receipt of proceeds by the owner from such
                      production. Payment shall be made to the Payee by the
                      Owner no later than the 45th calendar day following the
                      last day of each month. In calculating gross proceeds
                      for determining the


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                      amount of the royalty payment, production will be
                      calculated by the Owner for each calendar month, the
                      price of gold shall be the simple average of the London
                      Bullion Market Afternoon Fix on each day during the
                      relevant month on which such determination is made.

                      The Owner shall pay the Royalty, at the Payee's option,
                      either:

                      (A) by converting the Royalty payable in cash to gold
                      bullion (at the price of gold determined herein for the
                      month to which the payment relates) and deliver directly
                      to the Payee's account as directed in writing to the
                      Owner by the Payee, or

                      (B) by cheque or bank draft payable to the Payee at its
                      principal place of business as specified in subsection
                      17 (b), or in such other manner or place as specified in
                      writing by the Payee.

                      The Payee shall provide the Owner with written notice of
                      its election to receive payment in gold bullion no later
                      than the first day of the calendar month for which the
                      Payee wishes payment in bullion to commence.

          4.   The Owner and the Payee also agreed to amend the notice
               provisions in subsection 17(h) as follows:

                      17 (h) Notice

                              (i)  Subject to the payment provisions of this
                                   Agreement or any schedule hereto, all
                                   notices designations or other documents
                                   required or authorized by the terms of this
                                   Agreement shall be in writing and shall be
                                   personally delivered or mailed in Canada by
                                   registered or certified mail, postage
                                   prepaid, return receipt requested or
                                   telecopied in a manner which confirms
                                   transmission to the recipient, addressed as
                                   follows:

                              (A)  if to the Owner at:
                                       Meston Resources Inc.
                                       1155, University St., Suite 1405
                                       Montreal, Quebec H313 3A7

                                       Telecopier No.: (514) 875-9764

                                   with a copy to:

                                       Campbell Resources Inc.
                                       161 Bay Street, Suite 3750, P.O. Box 703
                                       Toronto, ON M5J 2S1

                                       Telecopier No.: (416) 367-3294


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                              (B)  if to the Payee at:
                                       Repadre Capital Corporation
                                       130 Adelaide St. West, Suite 2520
                                       Toronto, ON M5H 3P5

                                       Telecopier No.: (416) 365-8065


                              (ii) Any of the parties may change its address
                                   for notice by giving the other parties
                                   notice of such change in the manner
                                   specified in this Section. Notices
                                   personally delivered shall be deemed made
                                   and received on the date of such delivery.
                                   Notices given by mail in the manner
                                   specified in Section 19(g) shall be deemed
                                   to have been made, delivered and received
                                   five days after the date of mailing. A
                                   notice telecopied in the manner specified
                                   in Section 19(g) shall be deemed to have
                                   been made and received on the First
                                   business day following the day on which it
                                   was sent.

        5.     The Owner and the Payee agree to execute and deliver any
               further documents which may be necessary or desirable in order
               to reflect this amendment in the floating change trust deed
               issued pursuant to Section 18 of the Royalty Agreement and
               registered against title of the Property.

        6.     The Owner and the Payee confirm that other than the amendments
               set out above, the Royalty Agreement continues in full force
               and affect and there are no other amendments or agreements oral
               or otherwise.

               IN WITNESS WHEREOF the parties hereto have executed this
               Amending Agreement as of the day and year first above written.






               Signed in the      )            MESTON RESOURCES INC.
               presence of:       )
                                  )
                  [SIG]           )
               ----------------   )            Per:   [SIG]
               Witness            )                -------------------
                                  )                                c/s
               Signed in the      )            REPADRE CAPITAL CORPORATION
               presence of:       )
                                  )
                  [SIG]           )
               ----------------   )            Per:    [SIG]
               Witness            )                -------------------
                                                                   c/s