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                                                                   Exhibit 10.18

                          PURCHASE AND SALES AGREEMENT

This Purchase and Sales Agreement ("Agreement") is made and entered into as of
the 28th day of August of 2000, between MINERA ANDES S.A., represented by Mr.
Jorge Vargas, domiciled at Peru 930, Piso 2(o), 5500, Mendoza, Argentina
(hereinafter "MA" ), and MINERA EL DESQUITE S.A. , represented by Mr. Carlos J.
Miguens, domiciled at Av. Alem 1050, 6th floor, Capital Federal, Argentina
(hereinafter "MED").

                                     Recital

A.    MA holds mineral rights and cateos on the following property (hereinafter
      the "PROPERTY") described in Appendix I attached hereto :

      i.)   Cateo "Willimanco" (Expediente No 13.105/97)

B.    MA desires to sell its interest in such PROPERTY and MED desires to
      purchase such interest in the PROPERTY and related rights and agreements
      on the terms and subject to the conditions contained in the Agreement.

                                    Agreement

Now, therefore, for and in consideration of mutual covenants contained herein,
the parties agree as follows:

ARTICLE ONE: Purchase Price and Payment

1.1   MED will pay to MA, the sum of US$1,000,000 payable as set forth below
      (all dollar amounts stated herein shall be in United States dollars) and
      shall be payable to MA as provided for in Article 13.1: (i) upon signing
      this Agreement, the sum of US$40,000; (ii) on or before 6 months from the
      date of this Agreement, the sum of US$40,000; (iii) on or before 12 months
      from the date of this Agreement, the sum of US$80,000; (iv) on or before
      18 months from the date of this Agreement, the sum of US$80,000; (v) on or
      before 24 months from the date of this Agreement, the sum of US$80,000;
      (vi) on or before 30 months from the date of this Agreement, the sum of
      US$80,000; (vii) on or before 36 months from the date of this Agreement,
      the sum of US$120,000; (viii) on or before 42 months from the date of this
      Agreement, the sum of US$120,000; (ix) on or before 48 months from the
      date of this Agreement, the sum of US$360,000.

      Notwithstanding the above mentioned, MED may cancel the Purchase Price
      balance in any time within 48 months from the date of this Agreement.


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1.2   If any of the dates for payment established in Article 1.1 above should
      fall on a holiday, non-working or non-business day, such payment will be
      made on the first business or working day following that date.

1.3   Within 30 days after MED has made all the payments established in Article
      1.1. above MA shall assign and transfer to MED all rights, title and
      interest MA may have in and to the PROPERTY and to perform any act or
      activity that may be necessary to register such assignment in the records
      of the Mining Registry as provided in Article 3.1. below.

ARTICLE TWO: Production Royalty

2.1   Through the useful life of any mine within the PROPERTY developed, MED
      will pay to MA a production royalty equivalent to two percent (2.0%) "Net
      Smelter Return Royalty" on the terms and conditions established in
      Appendix II -attached hereto (hereinafter "Royalty").

2.2   Should MA wish to transfer its right to the Royalty, it will give notice
      in writing to MED of the transfer desired to be performed, indicating the
      name and address of the acquirer, the price and terms of sale.

ARTICLE THREE: Grant of Rights

3.1   MA agrees to give notice to the Direction of Mines of the Province of
      Chubut, by Public Notary, of this Purchase and Sales Agreement , in order
      to proceed to register such notice in the respective records and carry out
      all the other formalities that may be required. MA will also prepare a
      letter to the Direction of Mines requesting that MED be granted the same
      rights granted MA regarding the PROPERTY.

3.2   If for any reason the Direction of Mines will not accept this Agreement
      and it can not be registered, without conditions, within sixty (60) days
      in the respective records in the name of MED after first giving written
      notice to MA, MED may elect to terminate this Agreement and be released
      from the obligations resulting therefrom. Such election must be made
      within 90 days of the date of this Agreement.

3.3   If the Agreement is terminated as provided for in Article 3.2. , MA agrees
      to return to MED, within a period of not more than thirty (30) days from
      notification of termination, the initial payment of US$40,000 made by MED.


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ARTICLE FOUR: Termination by MED

4.1   At its own discretion and at any time, after giving written notice to MA
      at least 10 days in advance, MED may terminate this Agreement and shall
      reassign to MA the rights subject to this Agreement, and in good standing
      with the Direction of Mines of the Province of Chubut.

      a)    MA will retain all sums of money that, for any reason, were paid by
            MED prior to such termination and reassignment under this Agreement.

      b)    The obligation of MED to make the payments pending pursuant to
            Articles 1.1 and 2.1 of this Agreement, will be extinguished 10 days
            after the date of the notice of termination.

      c)    MED will deliver to MA copies of all technical information obtained
            in the area subject of this Agreement.

      d)    MED will give notice in writing to the Direction of Mines of the
            Province of Chubut of its decision to terminate the Agreement
            established herein and MED agrees to pay any and all taxes and rates
            that may be due.

      e)    MED may remove from the area described in Appendix I the movable
            properties, equipment, instruments, machinery, components and other
            property.

      f)    MED may remove from the area all the improvements which are
            susceptible to being removed.

      g)    MED shall remain responsible for reclamation of all disturbances
            caused by its activities in the area, on any other contingent
            environmental liabilities that may arise as a result of its
            activities.

      h)    MED shall remain responsible for any existing or contingent
            liabilities which arise from its occupancy of surface lands and any
            and all agreements with surface landowners.

ARTICLE FIVE: Rates, Taxes, Rent, Work Commitment

5.1   The provincial taxes and the municipal rates accrued until the date of the
      execution of the Agreement, will be paid by MA, thereafter to be paid by
      MED.

5.2   The mining rent (canon) accrued until the date of this Agreement will be
      paid by MA, thereafter to be paid by MED.

5.3   Any Stamp Tax that is assessed on this agreement will be paid by MED.

5.4   MED may withhold from payments due MA those sums due to MED for the
      payments that must be made as provided for in this Article 5 which are for
      the account of MA and have not been paid by it.


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5.5   MED shall be responsible for any and all work commitments that may be
      required by the Direction of Mines for the cateos and for any new mines
      that may be developed during the term of this agreement.

ARTICLE SIX: Assignment of Rights

6.1   MED may assign this agreement without needing a consent of MA. Prior to
      any assignment being effective, the new assignee will agree in writing to
      be bound by all the terms and conditions of this agreement, and
      specifically as provided for in Articles 1.1, 2.1, and 5 of the Agreement.

ARTICLE SEVEN: Terms of Payment

7.1   The payment of any sums of money, other than those established in Article
      5.4 above, that MED owes to MA must be made by transfer to MA's account
      provided for in Article 13.1. Each party will be responsible for their own
      taxes, assessments, charges and rates applicable to the payments.

ARTICLE EIGHT: Representations and warranties of MA and MED

8.1   MA represents, assures and warrants that:

      a)    It is the only title holder, beneficiary and owner of the mining
            rights subject to this Agreement and which are indicated in Appendix
            I, and that the area corresponds to what is stated by the Register
            of the Director of Mines of Province of Chubut in the sketch
            attached;

      b)    The formalities of the mining records described in Appendix I of the
            Direction of Mines of the Province of Chubut do not record any
            irregularities and they are under formal proceedings, according to
            the legal and regulatory provisions applicable thereto.

      c)    It is legally authorized to enter into this Agreement, and MA is not
            inhibited, nor are the rights herein transferred, subject to
            embargo, easement, encumbrance of rights of third parties that
            prevent, condition, or restrict the free availability of the mining
            rights subject thereof, nor has it encumbered, assigned and/or
            transferred in any way to third parties, fully or partially, such
            rights or petitions granted by the Mining Authority or requested
            from it.


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      d)    There are no known preexisting and/or subsisting mining rights of
            third parties with respect to the mining rights herein assigned, nor
            present or imminent claims, nor basis for claims, and it has no
            knowledge that there are third parties that claim rights or that
            could in some way file an objection against the rights subject to
            this Agreement.

      e)    All the taxes and/or rates (including the rent) have been paid in
            connection with the mining rights that are assigned hereby, and
            there is no sum owing for any concept;

      f)    If MA hereafter acquires any interest in any part of the area of the
            PROPERTY ( "the area" ) or over zones that are free or become freed
            within the area, either personally or through third parties, such
            interest shall be deemed a part of this Agreement and the
            description shall be deemed amended to include such interest.

      g)    There is no known environmental disturbance on the PROPERTY subject
            to this Agreement.

8.2   If MED hereafter, and for a period of 2 years after the termination of
      this Agreement, acquires any interest in any part of the area or over
      zones that are free or become freed within the area, either personally or
      through third parties, such interest shall be deemed a part of this
      Agreement and the description shall be deemed amended to include such
      interest. This specifically includes any manifestaciones de descubrimiento
      filed by MED or reacquisition of any land dropped as a result of Direction
      of Mines required reduction of cateo size.

ARTICLE NINE: Indemnity

9.1   MED shall indemnify and save harmless MA from and against any and all
      claims, demands, expenses (including attorney fees), suits or causes of
      action in law or equity for damages and injuries (including death)
      occurring on or about the PROPERTY and arising solely and directly out of
      MED's operations on the PROPERTY.

ARTICLE TEN: Default

10.1  In the event of default in the payment of the price established in Article
      1.1, MA must give notice in writing to MED demanding payment of the sum
      owed plus interest (interest shall be calculated at 12% per annum) for a
      period of not less than fifteen (15) business days since the date when the
      payment was due.


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10.2  If the sums owed by virtue of Article 1.1 are not paid as established
      herein, MA may terminate this agreement due to default in the payment
      obligation, in which case:

      a)    MA will keep all the payments made by MED, regardless of the nature
            or reason.

      b)    MED must deliver to MA the possession of the area within ninety (90)
            days from the date of termination of the Agreement, for which
            purpose it binds itself also to formalize the corresponding
            assignment within the same period for the purpose of reinstating the
            mining rights herein assigned.

      c)    MED may remove from the area all its PROPERTY and all the
            improvement susceptible of being removed within the same ninety (90)
            day period.

      d)    MED shall remain responsible for the reclamation of all disturbances
            caused by MED's activities on the PROPERTY.

10.3  In the event MED does not pay the Royalty provided for in Article 2.1 in
      the periods therein established, after sending written notice to correct
      such default in a period of not less than 15 days, MA may file the
      corresponding action to claim payment. In no event will MA claim the
      termination of the Agreement or require the assignment of the mining
      rights herein assigned for this reason unless and until the resolution of
      any conflict as provided in Article 20 in favor of MA and MED continues to
      not pay the Royalty.

10.4  MED may during the period of sixty (60) days following the signing of this
      Agreement investigate the representations and warranties made herein by
      MA. Should any of these representations and warranties be inaccurate or
      false, MED may (i) opt to terminate this Agreement and claim return of the
      sums previously paid, or (ii) keep it effective and continue with the
      existing terms of this Agreement.

ARTICLE ELEVEN: Cooperation in Administrative and Judicial Proceedings

11.1  MA binds itself to provide its cooperation and to execute any documents
      that may be required at the request of MED in the fulfillment of all the
      administrative and judicial proceedings enforceable by the competent
      authorities and the registration of the mining rights inherent to the
      applications for prospecting, permits and manifestations of discovery.


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ARTICLE TWELVE: Language; Governing Law

12.1  This Agreement is executed in English and English shall be the language to
      govern. A Spanish language translation of this Agreement approved by the
      parties shall be recorded in the Mining Registry of the proper Argentine
      jurisdiction. The cost of such translation and registration shall be borne
      and paid by MED. All matters concerning title to Agreement Property,
      including the acquisition, transfer and abandonment of mineral, surface
      and water rights, and contract law shall be governed by Argentinean law.

ARTICLE THIRTEEN: Place of Payment

13.1  MED promises to make the agreed payments by cash, check or wire transfer
      in United States dollars to the bank account specified by MA indicated
      below

                                    Bank Name : Washington Trust Bank
                                    Routing #:  125100089
                                    Account # : 1001415116
                                    Company :   Minera Andes Inc

ARTICLE FOURTEEN: Notices

14.1  All notices required or permitted to be given by a party under this
      Agreement shall be in writing and in the English language, and (unless
      some other mode of giving notice is specified or accepted in writing by
      the recipient) shall be effective (a) when personally delivered during
      normal business hours to the addressee at its principal address, (b) on
      the date of receipt specified in any return receipt, if it shall have been
      deposited in the mails, certified or registered with return receipt
      requested and postage thereon fully prepaid, addressed to the addressee at
      its principal address or (c) on the day it shall have been given by
      facsimile transmission to the addressee at its principal address,
      whichever otherwise specified by notice, the addressee for any notice
      shall be:

                     MA in:
                      Mr. Jorge Vargas
                      Peru 930, Piso 2(o)
                      5500, Mendoza, Argentina

                     MED in:
                      Mr. Diego Bauret
                      Av. L. N. Alem 1050, Piso 6
                      ( 1001 ) Ciudad de Buenos Aires
                      Capital Federal, Argentina


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ARTICLE FIFTEEN: Binding Effect

15.1  This Agreement shall be binding upon and shall inure to the benefit of the
      parties and their respective legal successors and permitted assigns.

ARTICLE SIXTEEN: Entire Agreement

16.1  This Agreement, including the scheduled attached hereto, sets forth the
      entire understanding of the parties with respect to the matters set forth
      herein as of the date hereof and supersedes all prior oral or written
      discussions and understandings between them.

ARTICLE SEVENTEEN: Construction and Interpretation

17.1  This Agreement is the result of negotiations between the parties, and the
      terms and provisions hereof shall be interpreted and construed in
      accordance with their usual and customary meanings. The captions or
      headings of articles or sub-articles of this Agreement are for purposes of
      reference only and shall not limit or define meaning of any provision of
      this Agreement.

ARTICLE EIGHTEEN: Amendments, Waivers, etc.

18.1  This Agreement may not be amended or modified except by a written
      instrument signed by all of the parties. No party shall be bound by any
      modification, amendment of this Agreement or waiver of any provision
      hereof unless such modification, amendment or waiver is set forth in a
      written instrument signed by each of the parties. Except as otherwise
      provided in this Agreement, failure on the part of any party to exercise
      any right hereunder or to insist upon strict compliance by any other party
      with any of the terms, covenants or conditions hereof shall not be deemed
      a waiver of such right, term, covenant or condition. No provision of this
      Agreement shall be construed to be a waiver by any of the parties of any
      rights or remedies such party may have against any other party for failure
      to comply with the provisions of this Agreement and, except as provided in
      Article 20 or otherwise expressly provided in this Agreement, no remedy or
      right herein conferred is intended to be exclusive of any other remedy or
      right, but every such remedy or right shall be cumulative and shall be in
      addition to every other remedy or right herein conferred or now or
      hereafter existing at law or in equity.


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ARTICLE NINETEEN: Further Assurances

19.1  Either party, at any time upon request of the other, shall execute and
      acknowledge in form required by law for recording or registering with the
      proper person and shall deliver to the requesting party such notices,
      deeds or other instruments incorporating, referring to or carrying out the
      provisions of this Agreement as the requesting party may reasonably deem
      necessary in order to preserve and protect its interest under this
      Agreement or to effectuate the provisions hereof.

ARTICLE TWENTY: Arbitration

20.1  Any dispute, controversy or claim arising out of or relating to this
      Agreement or the subject matter of this Agreement, or the execution,
      validity, interpretation, implementation, breach or termination of this
      Agreement shall be settled by non-binding mediation or by binding
      arbitration in accordance with the rules of Conciliation and Arbitration
      of the International Chamber of Commerce, being conducted in English in
      New York, New York, USA. All notices in connection with the arbitration or
      mediation, including the notice of arbitration or mediation and the
      response thereto, shall be served in the same manner as provided for
      notices generally under this Agreement.

IN WITNESS WHEREOF, the Parties hereto have caused this Agreement to be executed
by their respective officers and or representatives thereunto duly authorized as
of the date first above written.

MINERA ANDES                                   MINERA EL DESQUITE S.A.


/s/ Jorge Vargas                               /s/ Carlos Miguens
-----------------------                        ------------------------
By: : Mr. Jorge Vargas                         By : Mr. Carlos Miguens
Its:  President                                Its: President


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                                 A P P E N D I X


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APPENDIX I - Description and documentation of the property and map of location.

      Cateo "Willimanco" (Expediente No 13.105/97)

(LOCATION MAP)


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APPENDIX II - PRODUCTION ROYALTY - NET SMELTER ROYALTY

      In the event that MED mines and sells minerals from the PROPERTY, MED
shall, subject to all of the terms and conditions, provisions and agreements in
said Agreement, pay to MA percentage royalty payments equivalent to two percent
(2.0%) of the amount of the payments received by MED from the smelter or other
purchaser for the ores mined and removed from the PROPERTY described on Appendix
I and sold either in their raw, crude form, or as concentrates, less the
following deductions: (1) the deductions made by purchaser for sampling, assays
and penalties; (2) less all costs of freight, transportation and haulage; (3)
less any taxes attributable to MA's interest including, but not limited to, any
production taxes, severance taxes, and sales privilege and other taxes measured
by production or the value of production; and (4) less all smelting costs,
refining costs, treatment charges and penalties for impurities and charges for
refining, marketing and selling.

      If the ores shall be sold in their crude state (or as concentrates), then
the above stated percentage shall be applied to their fair market value in the
area of the PROPERTY of crude ore of like grade and quality in raw form at the
mine before any milling, treatment or beneficiation. In the event there is an
independent smelter or other purchaser reasonably available to MED at the time
of use by MED of the ore or concentrate, then said fair market value shall be
determined by amounts of which would have been realized (less the deductions
provided above) had the sale been made to such smelter or other purchaser.

      If any of the ore mined and removed from the PROPERTY by MED is upgraded,
processed, or otherwise treated in any way for MED pursuant to a custom milling
or processing arrangement, title to the crude ore shall be deemed to have been
beneficiated, processed or treated by MED.

      The term "concentrates" as used herein means the product derived from
beneficiation of crude ores through smelting, refining and/or any other
treatment processes to upgrade ore or more of the valuable constituents thereof.

      All of the payments provided in this Appendix II shall be due and payable
within thirty (30) days after the end of each calendar quarter within which ores
or concentrates have been mined and removed from the PROPERTY and sold or used.
Such payments shall be accompanied or preceded by statements indicating the
quantities and values of the ores mined and removed. Payment of the amount due
under any statement shall not prejudice the right of MA to protest or question
the correctness thereof. All statements rendered to MA by MED shall be
conclusively presumed to be true and correct after one hundred eighty (180) days
from the end of the calendar quarter to which such statement applies, unless
within said one hundred eighty-day period, MA takes exception thereto and makes
written claim on MED for adjustment. Failure on the part of MA to make such
claim for adjustment in such period shall establish the correctness and preclude
the filing of exceptions thereto or making of claims for adjustment thereon.


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