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                                                                   EXHIBIT 10.12


                              AMENDED AND RESTATED
                               GUARANTY AGREEMENT

         This agreement is made and entered into as of the 1st day of September,
2000, by and between AmerAlia, Inc., a Utah corporation whose address is 311
Raleigh Road, Kenilworth, Illinois 60043 ("AmerAlia") and Jacqueline Mars as
trustee for the Jacqueline Badger Mars Trust, whose address is 6885 Elm Street,
McLean, Virginia 22101 (the "Trust") to amend and restate in their entirety
certain previous guaranty agreements entered into between the Trust and AmerAlia
as described in Recital B.

                                    RECITALS

A.       AmerAlia has commenced operations necessary to build a plant for the
         production of sodium bicarbonate on property near Rifle, Colorado (the
         "Rock School Project"), and is seeking permanent financing to permit
         the Company to commence construction activities.

B.       To assist AmerAlia in securing financing for its corporate operations
         and the Rock School Project, the Trust has guaranteed loans to AmerAlia
         from Bank of America, N.A. (previously NationsBank) totaling
         approximately $7,326,000 in principal amount, plus accrued interest,
         and the Trust and AmerAlia have entered into three Guaranty Agreements
         relating to such loans as follows:

         (1)  Guaranty Agreement dated September 13, 1999, relating to a loan of
              approximately $4,200,000 in principal amount (the "Original
              Loan");

         (2)  Guaranty Agreement dated January 21, 2000, relating to a loan of
              approximately $1,000,000 in principal amount; and

         (3)  Guaranty Agreement dated June 30, 2000, relating to a loan of
              approximately $2,126,000 in principal amount (which funds were
              used, in part, to pay accrued interest on the previous loans),

         which are referred to collectively as the "Previous Guaranties."

C.       The Trust's compensation for entering into the Previous Guaranties is
         due and payable only following AmerAlia's announcement of permanent
         financing from TIAA-CREF or other lender, which announcement has not
         been made because the permanent financing has not been secured.

D.       The Original Loan has matured, and the Trust is willing to extend its
         guaranty which will result in the Bank extending the maturity date of
         the Original Loan and the loans involved in the other Previous
         Guaranties, and AmerAlia desires that the Trust extend its guaranty.

E.       The Trust is willing to facilitate the extension of the Original Loan
         and the other loans through September 14, 2001, and to provide for the
         payment of the fees required by the Previous Guaranties and this
         Agreement herein; and

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F.       AmerAlia's board of directors has determined that such an extension, on
         the terms and conditions set forth herein, is in the best interests of
         AmerAlia and its shareholders.

         NOW, THEREFORE, in consideration of the mutual promises and covenants
contained herein, and for other good and valuable consideration the receipt and
sufficiency whereof is hereby acknowledged, AmerAlia and the Trust agree as
follows:

1.       The Previous Guaranties are hereby modified in their entirety and
         incorporated herein. The Previous Guaranties are of no further force or
         effect.

2.       AmerAlia has filed certain loan applications with the Bank, and will
         file such applications as may be necessary for the Bank to extend the
         loans represented by the Previous Guaranties to and until September 14,
         2001.

3.       The Trust will execute and deliver to the Bank such forms as may be
         necessary or appropriate to provide a guaranty for the repayment of
         such loans in a form that is satisfactory to the Bank and to the Trust,
         and is consistent with this Agreement (the "Guaranty").

4.       AmerAlia will apply the net proceeds of any equity financing to repay
         the loans from the Bank, and the amount of the Guaranty will be reduced
         to the extent of such repayments.

5.       AmerAlia will pay the Trust compensation (the "Trust's Fee") for
         executing and delivering the Guaranty to the Bank in an amount equal to
         15% of the actual amount guaranteed, payable in shares of AmerAlia's
         restricted common stock calculated as follows:

         (a)  If AmerAlia issues a public announcement of a commitment for
              permanent financing from any person before the close of business
              on September 14, 2001 (the "Announcement"), AmerAlia will pay the
              Trust's Fee in shares of AmerAlia's restricted common stock valued
              at the average closing price as reported by The Nasdaq Stock
              Market, Inc. SmallCap Market for the 30 days following the
              Announcement. For example, if the amount guaranteed is $7,326,000
              and the average price is $2.50, AmerAlia will issue 439,560 shares
              of restricted common stock to the Trust. The shares will be issued
              to the Trust within three business days of this determination.

         (b)  If AmerAlia does not make the Announcement before the close of
              business on September 14, 2001, AmerAlia will pay the Trust's Fee
              in shares of AmerAlia's restricted common stock valued at the
              average of the ten highest closing prices as reported by The
              Nasdaq Stock Market, Inc. SmallCap Market for the calendar year
              2000 through August 31, 2000 (which average price is $3.34).

6.       If the Trust makes any payment to the Bank under the Guaranty, AmerAlia
         will indemnify and hold the Trust harmless for any such payment, and
         for all other costs and expenses, including reasonable attorneys' fees
         incurred in connection therewith.

7.       The Trust acknowledges that such shares, when issued, will be
         restricted as that term is defined in Rule 144 of the Rules and
         Regulations promulgated by the Securities and Exchange Commission. The
         Trust further acknowledges, represents and warrants to AmerAlia that:

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         (a)  The Trust is an 'accredited investor' as that term is defined
              in Section 2(a)(15) of the Securities Act of 1933 (the "1933 Act")
              and Rule 215 thereunder, and in Rule 501(a) of Regulation D of the
              1933 Act.

         (b)  AmerAlia has given the Trust and its legal, financial, tax, and
              investment advisors the opportunity to ask questions of and to
              receive answers from persons acting on AmerAlia's behalf
              concerning the terms and conditions of this transaction and the
              opportunity to obtain any additional information regarding
              AmerAlia, its business and financial condition which AmerAlia
              possesses or can acquire without unreasonable effort or expense
              including (without limitation) all minutes of the meetings of the
              Board of Directors of AmerAlia or committees thereof, and other
              relevant documents requested by the Trust. In addition, the Trust
              has spoken with the independent auditors for AmerAlia and has made
              financial or other inquiries as the Trust or its advisors have
              deemed necessary or appropriate in the conduct of the Trust's due
              diligence investigation.

         (c)  The Trust acknowledges and understands that, although there is
              currently a market for AmerAlia's common stock, the market is
              dependent on a number of factors beyond the control of AmerAlia
              and may not continue. Furthermore the Trust acknowledges that
              although AmerAlia believes that it is in compliance with all
              requirements for continued listing of the Common Stock on the
              Nasdaq SmallCap Market, continued listing on the Nasdaq SmallCap
              Market is subject to a number of objective and subjective
              criteria. Although AmerAlia believes it is in material compliance
              with all objective criteria, there can be no assurance that the
              staff of the Nasdaq SmallCap Market may not reach a different
              conclusion or that the Nasdaq staff may not reach a conclusion
              that AmerAlia is, for some reason, not in compliance with
              subjective criteria which is not specified in the rules applicable
              to the Nasdaq SmallCap Market.

         (d)  The Trust understands that the securities being acquired hereby
              are and will continue to be restricted securities within the
              meaning of Rule 144, and applicable state statutes. The Trust
              consents to the placement of an appropriate restrictive legend or
              legends on any certificates evidencing the securities and any
              certificates issued in replacement or exchange therefor and
              acknowledges that AmerAlia will cause its stock transfer records
              to note the restrictions.

              o     The Trust must bear the economic risks of the investment in
                    the securities for an indefinite period of time because they
                    have not been registered under the 1933 Act or any state
                    securities laws;

              o     As "restricted securities" (unless registered for resale or
                    another exemption from registration is available for any
                    transfer), the securities must be held for a minimum of one
                    year following the purchase. Thereafter, the securities may
                    be sold in only limited amounts in a specified manner in
                    accordance with the terms and conditions of Rule 144 (the
                    "Rule") if the Rule is applicable (there being no
                    representation by AmerAlia that it will be applicable). In
                    case the Rule is not applicable, any sales may be made only
                    pursuant to an effective registration statement or an
                    available exemption from registration.

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              o     The securities cannot be sold unless they are registered
                    under the 1933 Act and any applicable state securities laws
                    or unless an exemption from the registration requirements is
                    available. To the extent that AmerAlia files any
                    registration statement under the 1933 Act (not including a
                    registration statement on Form S-4, S-8, S-11, or other
                    inappropriate form), AmerAlia will endeavor to include the
                    Securities in such registration statement, subject to any
                    requirements that may be imposed by any underwriter named in
                    the registration statement (which requirements may include,
                    but are not limited to, a delay in the ability of the
                    selling security holder to sell the shares, a requirement
                    that any sales be made through the underwriter, or a
                    prohibition on any sales by the selling security holder
                    pursuant to the registration statement in certain specified
                    circumstances, in the underwriter's sole discretion).

         (e)  The Trust has reviewed the terms of this agreement and the
              transaction contemplated by this agreement with its legal,
              investment, tax, and financial advisors to the extent the Trust
              has deemed such consultation appropriate. The Trust has also
              consulted with such advisors with regard to the advisability of
              this investment to the extent the Trust has deemed such
              consultation to be appropriate. The Trust acknowledges that
              AmerAlia has advised the Trust that it recommends that the Trust
              obtain advice and consultation. The Trust further acknowledges
              that it has neither sought nor received any advice from AmerAlia
              or any of its agents or affiliates with respect to any aspect of
              this Agreement.

         (f)  The Trust acknowledges that the investment contemplated herein
              is one of significant risk, and there can be no assurance that the
              securities will ever be valuable. The Trust hereby represents that
              the investment in the securities is a suitable investment for it,
              taking into consideration the restrictions on transferability and
              the other considerations affecting the securities and AmerAlia as
              described herein and in AmerAlia's reports filed with the
              Securities and Exchange Commission pursuant to the Securities
              Exchange Act of 1934, as amended (the "1934 Act").

         (g)  The Trust acknowledges that the acquisition of the securities
              as contemplated herein will impose certain reporting obligations
              on the Trust pursuant to Sections 13(d) and 16(a) of the 1934 Act,
              and may impose certain obligations under the Internal Revenue Code
              of 1986, as amended. The Trust will make all necessary filings.

8.       All notices under this Agreement are to be delivered by (i) depositing
         the notice in the mail, using registered mail, return receipt
         requested, addressed to the address below or to any other address as
         the party may designate by providing notice, (ii) telecopying the
         notice by using the telephone number set forth below or any other
         telephone number as the party may designate by providing notice, (iii)
         overnight delivery service addressed to the address below or to any
         other address as the party may designate by providing notice, or (iv)
         hand delivery to the individual designated below or to any other
         individual as the party may designate by providing notice. The notice
         shall be deemed delivered (i) if by registered mail, four (4) days
         after the notice is deposited in the mail, (ii) if by telecopy, on the
         date the notice is delivered, (iii) if by overnight delivery service,
         on the date of delivery, and (iv) if by hand delivery, on the date of
         delivery.


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              If to AmerAlia, to the address set forth in the first paragraph
              hereof, with a copy (which does not constitute notice) to:

                           AmerAlia, Inc.
                           818 Taughenbaugh Blvd
                           Rifle, CO 81650
                           Attn: Bill H. Gunn, President
                           Telecopy: 970-625-9134

              and to:

                           Norton A Lidstone, P.C.
                           Suite 850, The Quadrant
                           5445 DTC Parkway
                           Englewood, CO 80111
                           Attn: Herrick K. Lidstone, Jr., Esq.
                           Telecopy: 303-221-5553

              If to the Trust, to the attention of Vito Spitaleri (telecopy
              number) 410-827-4261) at the address set forth in the first
              paragraph hereof, with a copy (which does not constitute notice)
              to:

                           Hills & Stern
                           1200 Nineteenth Street, N.W.
                           Washington, D.C. 20036
                           Attn: Roderick M. Hills, Esq.
                           Telecopy: 202-822-1622

9.       General Provisions

         (a)  Complete Agreement. The parties agree that this Agreement is the
              complete and exclusive statement of the agreement between the
              parties, which supersedes and merges all prior proposals,
              understandings and all other agreements, oral or written, between
              the parties relating to this Agreement.

         (b)  Amendment. This Agreement may not be modified, altered or amended
              except by written instrument duly executed by both parties.

         (c)  Waiver. The waiver or failure of either party to exercise in any
              respect any right provided for in this Agreement shall not be
              deemed a waiver of any further right under this Agreement.

         (d)  Severability. If any provision of this Agreement is invalid,
              illegal or unenforceable under any applicable statute or rule of
              law, it is to that extent deemed omitted. The remainder of the
              Agreement shall be valid and enforceable to the maximum extent
              possible.


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         (e)  Governing Law. This Agreement and performance hereunder shall be
              governed by the laws of the State of Colorado.

Each party acknowledges that it has read and understands this Agreement and
agrees to be bound by its terms.


AmerAlia, Inc.                              The Jacqueline Badger Mars Trust





By:                                         By:
   ---------------------------                 ---------------------------
Bill H. Gunn, President                     Jacqueline Mars, Trustee


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