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                                                                    Exhibit 10.5

                                 PROMISSORY NOTE

$13,800,000                                                               [Date]

      FOR VALUE RECEIVED, the undersigned, [Ashanti Goldfields Company Limited],
a [Ghana] corporation (the "Maker"), promises to pay to Pioneer Goldfields II
Limited, (the "Seller") by wire transfer of immediately available Funds to the
account designated by the Seller in writing at least 5 days prior to the due
date for the relevant payment as set out below, the principal sum of Thirteen
Million Eight Hundred Thousand Dollars ($13,800,000) as agreed pursuant to the
Purchase Agreement dated [         ], 2000 among the Maker, the Seller and The
Pioneer Group, Inc. (the "Purchase Agreement").

      Principal payments by the Maker under this Note shall be paid as follows:

      1.    Two Million Five Hundred Thousand U.S. Dollars (US$2,500,000) on
            March 31, 2001;

      2.    Two Million Five Hundred Thousand U.S. Dollars (US$2,500,000) on
            March 31, 2002;

      3.    Three Million U.S. Dollars (US$3,000,000) on March 31, 2003;

      4.    Three Million Seven Hundred Fifty Thousand U.S. Dollars
            (US$3,750,000) on March 31, 2004; and

      5.    Two Million Fifty Thousand U.S. Dollars (US$2,050,000) on March 31,
            2005.

      Notwithstanding the foregoing, the obligation of the Maker to make any
such principal payments under this Note shall be subject to the terms of the
Purchase Agreement, including without limitation certain rights to make
deductions from such payments as specified therein.

      This Note shall become immediately due and payable without notice or
demand upon the occurrence at any time of a default in the payment or
performance of this obligation of the Maker to the holder, including the payment
when due of any principal under this Note. Upon the occurrence of such default,
the holder shall have then, or at any time thereafter, all of the rights and
remedies afforded by the Uniform Commercial Code as from time to time in effect
in the State of New York or afforded by other applicable law.

      All payment by the Maker under this Note shall be made without set-off or
counterclaim and be free and clear and without any deduction or withholding for
any taxes or fees of any nature whatever (except those rights to set-off
deduction or withholding for taxes or fees as provided in the Purchase
Agreement), unless the obligation to make such deduction or withholding is
imposed by law. The Maker shall pay and save the holder harmless from all
liabilities with respect to or resulting from any delay or omission to make any
such deduction or withholding required by law.

      The Maker agrees to pay on demand all costs of collection, including
reasonable attorney's fees, incurred by the holder in enforcing the obligations
of the Maker under this Note. Any rights of the holder under this Note to
payment for costs incurred by the holder in enforcing the obligations of the
Maker under this Note shall not be in addition to any rights of indemnification
under Section 14 of the Purchase Agreement.

      No delay or omission on the part of the holder in exercising any right
under this Note shall operate as a waiver of such right or of any other right of
such holder, nor shall any delay, omission or waiver on any one occasion be
deemed a bar to or waiver of the same or any other right on any future occasion.
The Maker of this Note regardless of the time, order or place of signing waives
presentment, demand, protest and notices of every kind and assents to any
extension or postponement of the time of payment or any other indulgence.

      This Note may be prepaid in whole or in part at any time or from time to
time. Any such


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prepayment shall be without premium or penalty.

      In accordance with Section 2.03(e) of the Purchase Agreement, this Note
may only be transferred to the Pioneer Group, Inc. or any other entity under the
common control of the Pioneer Group, Inc. With the consent of the Maker (which
consent may not be unreasonably withheld), the Seller may transfer this Note to
a company or entity not under common control of PGI.

      None of the terms or provisions of this Note may be excluded, modified or
amended except by a written instrument duly executed on behalf of the holder
expressly referring to this Note and setting forth the provision so excluded,
modified or amended.

      All rights and obligations hereunder shall be governed by the laws of the
State of New York.


                                            [ASHANTI GOLDFIELDS COMPANY LIMITED]


                                       By:
                                            -----------------------------------
                                            Name:

                                            Title:


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                  CONSENTS AND APPROVALS REQUIRED BY THE BUYER

Set out below is a true, correct and complete list of all consents and approvals
of third parties that are required in connection with the consummation by the
Buyer of the transactions contemplated by this Agreement:

      (a)   Under the Minerals and Mining Law, 1986 (as amended by the Minerals
            & Mining (Amendment) Act of 1994) a person cannot become a
            shareholder controller or a majority shareholder controller or an
            indirect controller of a mining company unless he has first served
            on the Minister of Mines, Minerals and Energy (the "Minister")
            written notice of his intention to do so and the Minister (in
            accordance with the advice of the Minerals Commission) has confirmed
            that he has no objections to such person becoming a shareholder
            controller or a majority shareholder controller or an indirect
            controller of a mine or the relevant time for such objection has
            elapsed.

      (b)   Consent of each of its lenders under Ashanti Goldfield Company
            Revolving Credit Facility (as amended), the Senior Bridge Credit
            Facility and AGC's hedge counterparties.

      (c)   Consent of the Government of Ghana, as owner of 10% of the issued
            and outstanding shares of Teberebie, to the planned transfer of
            certain assets of Teberebie to Gold Fields (Ghana) Limited and the
            creation of any new security or lien over the assets of Teberebie.

      (d)   Written agreement (on terms acceptable to AGC) with the shareholders
            of and lenders to its subsidiary, Ghanaian-Australian Goldfields
            Limited ("GAG") on the terms on which GAG's borrowings are to be
            rescheduled and the terms on which GAG will agree to process ore to
            be mined from PGL's Teberebie Mine.


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