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                                                                               .
                                                                               .
                                                                               .
                                                                     Exhibit 4.1

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[CANADIAN FLAG LOGO]            Consumer and                           Consommation et
                                Corporate Affairs Canada               Affaires commerciales Canada

CERTIFICATE OF INCORPORATION                                                                       CERTIFICAT DE CONSTITUTION

CANADA BUSINESS                                                                                    LOI REGISSANT LES SOCIETES
CORPORATIONS ACT                                                                                PAR ACTIONS DE REGIME FEDERAL

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        COMINCO FERTILIZERS LTD.                                                             288081-4

----------------------------------------------------------            -----------------------------------------------------------
Name of Corporation - Denomination de la societe                                           Number - Numero

I hereby certify that the above-mentioned Corporation,                Je certifie par les presentes que la societe mentionnee
the Articles of Incorporation of which are attached, was              ci-haut, dont les statuts constitutifs sont joints, a ete
incorporated under the Canada Business Corporations Act.              constituee en societe en vertu de la Loi regissant les
                                                                      societes par actions de regime federal.


                      Le directeur

                     /s/ [SIGNATURE]                                           DECEMBER 21, 1992 / LE 21 DECEMBRE 1992
                        Director                                             Date of Incorporation - Date de constitution

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<PAGE>
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<S>                                                            <C>

[CANADIAN FLAG LOGO]     CONSUMER AND               CONSOMMATION                          FORM 1                    FORMULE 1
                         CORPORATE AFFAIRS CANADA   ET CORPORATIONS CANADA       ARTICLES OF INCORPORATION    STATUTS CONSTITUTIFS
                                                                                        (SECTION 6)               (ARTICLE 6)
                         CANADA BUSINESS            LOI REGISSANT LES SOCIETES
                         CORPORATIONS ACT           PAR ACTIONS DE REGIME FEDERAL

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1- Name of Corporation                                        Denomination de la societe

   COMINCO FERTILIZERS LTD.
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2- The place in Canada where the registered office            Lieu au Canada ou doit etre situe le siege social
   is to be situated -

   Calgary, Alberta
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3 - The classes and any maximum number of shares              Categories et tout nombre maximal d'actions que la
    that the corporation is authorized to issue               societe est autorisee a emettre

    An unlimited number of Common Shares and an unlimited number of Preferred Shares having the rights, privileges, restrictions
    and conditions set out in Schedule 1 hereto.
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4 - Restrictions if any on share transfers                    Restrictions sur le transfert des actions, s'il y a lieu

    N/A
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5 - Number (or minimum and maximum number) of directors       Nombre (ou nombre minimum et maximum) d'administrateurs

    Minimum of three (3) and a maximum of fifteen (15)
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6 - Restrictions if any on business corporation may           Limites imposees quant aux activites commerciales que le societe peut
    carry on                                                  exploiter, s'il y a lieu

    N/A
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7 - Other provisions if any                                   Autres dispositions s'il y a lieu

   N/A
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7 - Incorporators - Fondateurs

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                             Address (include postal code)
Names - Noms                 Adresse (inclure le code postal)                   Signature
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WEBB, Ian A.                 900 - 200 Burrard Street                           /s/ Ian A. Webb
                             Vancouver, British Columbia, V7X 1T2
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FOR DEPARTMENTAL USE ONLY - A L'USAGE DU MINISTERE SEULEMENT                           Filed - Deposee
Corporation No. - No de la societe                                                      Jan - 5 1993
#288081-4

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CCA 7530-21-936-1385 (05-91) 46

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<PAGE>
                        CANADA BUSINESS CORPORATIONS ACT

                            ARTICLES OF INCORPORATION

                                     FORM 1

                                   SCHEDULE 1

                      RIGHTS, PRIVILEGES, RESTRICTIONS AND

                   CONDITIONS ATTACHED TO EACH CLASS OF SHARES

1.    The following rights, privileges, restrictions and conditions shall be
attached to the Common Shares of the Corporation:

      (a)   The holders of Common Shares shall be entitled to vote at all
            meetings of the shareholders of the Corporation, except meetings at
            which only the holders of Preferred Shares of one or more series are
            entitled to vote, and shall be entitled to one vote at all such
            meetings for each Common Share held.

      (b)   The holders of Common Shares shall be entitled to participate
            rateably in any dividends that may be declared by the directors on
            the Common Shares.

      (c)   If the Corporation is liquidated, dissolved or wound-up or makes any
            other distribution of its assets for the purpose of winding up its
            affairs, the holders of Common Shares shall be entitled to a pro
            rata share of the assets of the Corporation after payment of all
            liabilities, obligations and amounts payable in those circumstances
            to the holders of the Preferred Shares of the Corporation.

2.    The following rights, privileges, restrictions and conditions shall be
attached to the Preferred Shares of the Corporation as a class:

                                      - 1 -


<PAGE>

      (a)   The preferred Shares may be issued at any time or from time to time
            in one or more series, and the directors may by resolution fix the
            number of Preferred Shares in each series and determine the
            designation of and the rights, privileges, restrictions and
            conditions attaching to the Preferred Shares of each series subject
            to the rights, privileges, restrictions and conditions attached to
            the Preferred Shares as a class. A resolution under this
            subparagraph 2(a) may only be passed prior to the issue of shares of
            the series to which the resolution relates.

      (b)   The Preferred Shares shall be entitled to preference over the Common
            Shares of the Corporation and any other shares of the Corporation
            ranking junior to the Preferred Shares with respect to the payment
            of dividends and may also be given such other preferences over the
            Common Shares of the Corporation and any other shares of the
            Corporation ranking junior to the Preferred Shares as may be
            determined by the directors.

      (c)   No dividends (other than stock dividends in shares of the
            Corporation ranking junior to the Preferred Shares) shall at any
            time be declared or paid on or set apart for payment on any shares
            of the Corporation ranking junior to the Preferred Shares unless all
            dividends up to and including the dividend payable for the last
            completed period for which such dividends shall be payable on each
            series of Preferred Shares then issued and outstanding shall have
            been declared and paid or set apart for payment at the date of the
            declaration or payment or setting apart for payment on such shares
            of the Corporation ranking junior to the Preferred Shares nor shall
            the Corporation call for redemption or redeem or purchase for
            cancellation or reduce or otherwise pay off any of the Preferred
            Shares (less than the total amount then outstanding) or any shares
            of the

                                      - 2 -


<PAGE>

            Corporation ranking junior to the Preferred Shares unless all
            dividends up to and including the dividend payable for the last
            completed period for which dividends shall be payable on each series
            of Preferred Shares then issued and outstanding shall have been
            declared and paid or set apart for payment at the date of the call
            for redemption, purchase, reduction or other payment off.

      (d)   The Preferred Shares of each series shall rank on a parity with the
            Preferred Shares of every other series with respect to priority in
            payment of dividends and in distribution of assets in the event of
            the liquidation, dissolution or winding-up of the Corporation or any
            other distribution of the assets of the Corporation among its
            shareholders for the purpose of winding-up its affairs.

      (e)   If the Corporation is liquidated, dissolved or wound-up or makes any
            other distribution of its assets among its shareholders for the
            purpose of winding-up its affairs, the holders of the Preferred
            Shares shall be entitled to receive, before any distribution shall
            be made to the holders of the Common Shares, or any other shares of
            the Corporation ranking junior to the Preferred Shares, the amount
            paid up on each Preferred Share held by them, together with the
            fixed premium (if any) thereon, all accrued and unpaid cumulative
            dividends (if any and if preferential) thereon, which for this
            purpose shall be calculated as if the dividends were accruing on a
            day-to-day basis up to the date of distribution, whether or not
            earned or declared, and all declared and unpaid non-cumulative
            dividends (if any and if preferential) thereon. After payment to
            holders of Preferred Shares of the amounts so payable to them, they
            shall not be entitled to share in any further distribution of the
            property or assets

                                      - 3 -


<PAGE>

            of the Corporation except as specifically provided in the rights,
            privileges, restrictions and conditions attached to any particular
            series.

      (f)   Where any fixed cumulative dividends or amounts payable on a return
            of capital are not paid in full, the Preferred Shares of all series
            shall participate rateably with respect to accumulated dividends in
            accordance with the amounts that would be payable on those shares if
            all the accumulated dividends were declared and paid in full and on
            any return of capital in accordance with the amounts that would be
            payable on the return of capital if all amounts so payable were paid
            in full.

      (g)   The holders of the Preferred Shares shall not as of right be
            entitled to subscribe for, purchase or receive any part of any issue
            of shares, bonds, debentures or other securities of the Corporation
            now or hereafter authorized, or any rights to acquire the same,
            otherwise than in accordance with the rights, privileges,
            restrictions and conditions, if any, which may from time to time be
            attached to any series of Preferred Shares.

      (h)   So long as any Preferred Shares are outstanding, the Corporation
            shall not at any time without, in addition to any approval that may
            then be prescribed by applicable law, the approval of the registered
            holders of the Preferred Shares given in writing by the registered
            holders of two-thirds of the outstanding Preferred Shares or given a
            resolution passed at a meeting called and conducted in accordance
            with the second sentence of subparagraph 2(k) and carried by the
            affirmative vote of not less than two-thirds of the votes cast at
            the meeting, create any shares ranking prior to the Preferred Shares
            for the payment of

                                      - 4 -


<PAGE>

            dividends or the distribution of assets in the event of the
            liquidation, dissolution or winding-up of the Corporation or any
            other distribution of the assets of the Corporation among its
            shareholders for the purpose of winding-up its affairs.

      (i)   Except as provided in this paragraph 2 or as otherwise provided in
            the rights, privileges, restrictions and conditions attached to any
            series of Preferred Shares and except as otherwise required by law,
            the registered holders of the Preferred Shares shall not be entitled
            as a class to receive notice of or to attend or to vote at any
            meeting of shareholders of the Corporation unless and until the
            Corporation shall have failed to pay in the aggregate eight
            cumulative dividends on any series of Preferred Shares on the dates
            on which the same are to be paid in accordance with the provisions
            thereof, whether or not those dividends are consecutive and whether
            or not there are any moneys of the Corporation properly applicable
            to their payment. In the event of any such failure, the registered
            holders of the Preferred Shares shall have the right to receive
            notice of and to attend each meeting of shareholders of the
            Corporation at which directors are to be elected and that takes
            place more than 60 days after the date on which the failure first
            occurs (other than a separate meeting of the holders of another
            class or series of shares), and the registered holders of the
            Preferred Shares shall have the right to elect at each of those
            meetings, voting separately as a class, two directors out of
            whatever number of directors are to be elected at the meeting,
            provided that these rights of notice, attendance and election shall
            not apply at any meeting that takes place after the dividends are no
            longer in arrears.

                                      - 5 -


<PAGE>

      (j)   The rights, privileges, restrictions and conditions attached to the
            Preferred Shares as a class may be added to, changed or removed at
            any time or from time to time with, in addition to any approval that
            may then be prescribed by applicable law, the approval of the
            registered holders of the Preferred Shares given in writing by the
            registered holders of two-thirds of the Preferred Shares or given by
            a resolution passed at a meeting called and conducted in accordance
            with the second sentence of subparagraph 2(k) and carried by the
            affirmative vote of not less than two-thirds of the votes cast at
            the meeting.

      (k)   Except as otherwise provided in the rights, privileges, restrictions
            and conditions attached to any series of Preferred Shares and except
            as otherwise required by law, on any poll taken at any meeting of
            the registered holders of the Preferred Shares as a class or at a
            meeting of the registered holders of any one or more series of the
            Preferred Shares each registered holder of Preferred Shares entitled
            to vote, present in person or represented by proxy, shall be
            entitled, with respect to his or her shares of each series, to one
            vote in respect of each dollar, excluding any fraction of a dollar,
            of the product resulting from multiplying (i) the number of shares
            of the series held by the registered holder, by (ii) the issue price
            per share of the series. The formalities to be observed with respect
            to the giving of notice of and voting at any meeting of holders of
            Preferred Shares (including without in any way limiting the
            generality of the foregoing, the record dates for the giving of
            notice and the entitlement to vote), the quorum therefor and the
            conduct thereof shall, with the necessary changes and so far as
            applicable, be those from time to time prescribed by law, by the
            by-laws of the Corporation or by the directors for meetings of
            shareholders.


                                      - 6 -