<PAGE>
                                                                   EXHIBIT 10.24

                           SECOND AMENDMENT AGREEMENT
                                       TO
                     PALLADIUM AND PLATINUM SALES AGREEMENT


         THIS SECOND AMENDMENT AGREEMENT (this "Amendment"), is made and entered
into this 14th day of February, 2001, by and between STILLWATER MINING COMPANY,
a Delaware corporation, whose address is 1200 17th Street, Suite 900, Denver,
Colorado ("SMC") and GENERAL MOTORS CORPORATION, a Delaware corporation, whose
address is 100 Renaissance Center, Detroit, Michigan 48265-1000 ("GM").

         SMC and GM are parties to a Palladium and Platinum Sales Agreement
dated as of August 17, 1998 (as amended by the First Amendment Agreement to
Palladium and Platinum Sales Agreement dated as of November 20, 2000, the
"Original Contract," and, as the same may be amended from time to time, the
"Agreement"). SMC has requested that GM agree to certain amendments to the
Agreement, and GM has agreed to such request, subject to the terms and
conditions hereof .

         Accordingly, the parties hereto agree as follows:

         SECTION 1 Definitions; Interpretation.

         (a) Terms Defined in Agreement. All capitalized terms used in this
Amendment and not otherwise defined herein shall have the meanings assigned to
them in the Agreement.

         (b) Interpretation. Headings in this Amendment are for convenience of
reference only and are not part of the substance hereof.

         SECTION 2 Amendments to the Agreement.

         (a) Amendments. The Agreement shall be amended as follows, effective as
of the date hereof, upon satisfaction of the conditions set forth in Section 3:

                  (i) The definition of "Pricing Month" in, Section 1 of the
         Agreement shall be amended by deleting it in its entirety and by
         substituting the following therefor:



<PAGE>

                           "Pricing Month" means the month during which pricing
                  is determined pursuant to Section 4 of thus Agreement."

                  (ii) Section 3 of the Agreement shall be amended by deleting
         the first paragraph thereof in its entirety and by substituting the
         following therefor:

                           "Section 3. Quantity and Delivery. Beginning on
                  February, 2001, SMC will sell and deliver Metal FOB Delivery
                  Point, to be credited to GM's pool account, and GM will
                  purchase the quantities of Metal set forth in this Section 3,
                  which shall be released to the Delivery Point on the last
                  Business Day of the Pricing Month. All Metal to be sold in any
                  one calendar month shall be delivered to a single Delivery
                  Point unless GM has notified SMC by the 20th Business Day of
                  the Pricing Month that GM has elected to have the monthly
                  shipment split and delivered to more than one Delivery Point;
                  provided that SMC shall not be obligated to split a shipment
                  unless at least 5,000 Ounces of Palladium and/or Platinum are
                  to be shipped to each Delivery Point."

                  (iii) Section 3 of the Agreement shall be amended by deleting
         subsection (c) thereof in its entirety and by substituting the
         following therefor:

                           "(c) Notification of Estimated Annual Production and
                  of Actual Monthly Production. Not later than January 15th of
                  each Contract Year, SMC shall, for informational purposes
                  only, notify GM in writing of the Estimated Annual Production
                  for such Contract Year. Not later than the last Business Day
                  of the month preceding the Pricing Month, SMC shall notify GM
                  in writing of its Actual Monthly Production, which amount will
                  be priced during the next month, i.e. the Pricing Month, and
                  released to the Delivery Point on the last Business Day of the
                  Pricing Month. SMC will provide GM on a quarterly basis with a
                  certification from its Chief Financial Officer of Actual
                  Monthly Production amounts and will provide an annual
                  reconciliation of such amounts to SMC's Annual Report on Form
                  10-K.

                           By way of example, for delivery of Metal at the end
                  of February 2001, SMC will notify GM of the Actual Monthly
                  Production by the last Business Day in January 2001 and the
                  Metal

                                       2
<PAGE>
                  will be priced in February 2001 and released to the Delivery
                  Point on February 28, 2001."

                  (iv) Section 5 of the Agreement shall be amended by deleting
         it in its entirety and by substituting the following therefor:

                           "Section 5. Payment Terms. On the last Business Day,
                  of each Pricing Month, SMC will inform GM in writing via
                  facsimile as to the formula-based pricing computations set
                  forth in Section 4 above for the actual quantities of Metal to
                  be delivered by SMC pursuant to this Agreement during the
                  following month. Unless GM has provided SMC with Notice of
                  disagreement with the pricing computations, GM will forward
                  such payment amount for 100% of the actual quantities by wire
                  transfer to SMC (pursuant to written wire transfer
                  instructions which will be provided by SMC) within three
                  Business Days following the release of the Metal to the
                  Delivery Point. All payments will be made in U.S. Dollars. If
                  GM does not agree with SMC's pricing computations, GM shall
                  Notify SMC of such disagreement and the parties shall seek
                  resolution of such dispute as to the calculation of the
                  payment amount prior to the date payment is due:"

         (b) References Within Agreement. Each reference in the Agreement to
"this Agreement" and the words "hereof," "herein," "hereunder," or words of like
import, shall mean and be a reference to the Agreement as amended by this
Amendment.

         SECTION 3 Conditions of Effectiveness. The effectiveness of Section 2
of this Amendment shall be subject to the satisfaction of each of the following
conditions precedent:

         (a) Agreement SMC and GM shall have each received a signed counterpart
of this Amendment, or a facsimile copy thereof, signed by the other party
hereto.

         SECTION 4 Miscellaneous.

         (a) Agreement Otherwise Not Affected. Except as expressly amended
pursuant hereto, the Agreement shall remain unchanged and in full force and
effect and is hereby ratified and confirmed in all respects.

         (b) No Reliance. Each party hereto hereby acknowledges and confirms to
the other that such party is executing this Amendment on the basis of its own


                                       3
<PAGE>


investigation and for its own reasons without reliance upon any agreement,
representation, understanding or communication by or on behalf of any other
Person.

         (c) Binding Effect. This Amendment shall be binding upon, inure to the
benefit of and be enforceable by each party hereto and their respective
successors and assigns.

         (d) Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK UPON THE SAME TERMS AND
CONDITIONS AS THOSE SET FORTH IN SECTION 25 OF THE AGREEMENT.

         (e) Complete Agreement; Amendments. This amendment contains the entire
and exclusive agreement of the parties hereto with reference to the matters
discussed herein and therein. This Amendment supersedes all prior commitments,
drafts, communications, discussions and understandings, oral or written, with
respect thereto. This Amendment may not be modified, amended or otherwise
altered except, in accordance with the terms of Section 23 of the Agreement.

         (f) Severability. Whenever possible, each. provision of his Amendment
shall be interpreted in such manner as to be effective and valid under all
applicable laws and regulations. If, however, any provision of this Amendment
shall be prohibited by or invalid under any such law or regulation in any
jurisdiction, it shall, as to such jurisdiction, be deemed modified to conform
to the minimum requirements of such law or regulation, or, if for any reason it
is not deemed so modified, it shall be ineffective and invalid only to the
extent of such prohibition or invalidity without affecting the remaining
provisions of this Amendment, or the validity or effectiveness of such provision
in any other jurisdiction.

         (g) Counterparts. This Amendment may be executed in any number of
counterparts and by different parties hereto in separate counterparts, each of
which when so executed shall be deemed to be an original and all of which taken
together shall constitute but one and the same agreement.



                                       4
<PAGE>


         IN WITNESS WHEREOF, the parties hereto have duly executed this
Amendment, as of the date first above written.


                                            STILLWATER MINING COMPANY

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

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


                                            GENERAL MOTORS CORPORATION

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

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


                                       5