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                                                                   EXHIBIT 10.47

                                 PROMISSORY NOTE

US$ $1,800,000.00                                              February 15, 2001


                                    ARTICLE I
                               PAYMENT OBLIGATION

         FOR VALUE RECEIVED, the undersigned The UniMark Group, Inc., a Texas
corporation ("Maker"), promises to pay to the order of M&M Nominee, LLP
("Payee"), the sum of One Million Eight Hundred Thousand Dollars (US
$1,800,000.00), together with interest on the unpaid principal balance from time
to time outstanding at a rate per annum equal to twelve percent (12%). The
principal of and accrued interest on this Note shall be due and payable in
lawful money of the United States on the earlier of (a) July 31, 2001 or (b) a
Qualified Equity Financing (as defined below). As used herein a "Qualified
Equity Financing" shall mean the sale by Maker of equity securities or debt
securities, which may be convertible into equity securities of Maker, with net
proceeds to Maker in amount equal to the outstanding principal amount of this
Note.

         Maker shall have the right to prepay the principal of this Note in full
or in part at any time and from time to time without premium or penalty,
provided, however, that accrued interest shall be due and payable
contemporaneously with such prepayment of principal.

                                   ARTICLE II
                              AFFIRMATIVE COVENANTS

         So long as any of the principal of and accrued interest of this Note is
outstanding, or until the Payee consents to the contrary and the Maker receives
prior written approval to the contrary from the Payee, Maker will comply, or
cause compliance, with each of the following covenants:

         1. QUALIFIED EQUITY FINANCING V.3 USE OF PROCEEDS. Maker will pursue a
Qualified Equity Financing as soon as practical and to use the net proceeds from
such financing to immediately prepay the principal of, and accrued interest
under, of this Note in full.

         2. LIMITATION ON SENIOR INDEBTEDNESS V.3 USE OF PROCEEDS. Maker will
not incur any indebtedness senior in right of payment to the prior payment in
full in cash of the outstanding principal of and accrued interest on the Note,
except for (a) indebtedness of the Maker owed on the date hereof and interest
accruing thereon or (b) to provide working capital necessary for the proper
conduct of the Maker's business.

                                   ARTICLE III
                                EVENTS OF DEFAULT

         The following shall constitute Events of Default ("Event(s) of
Default"):

         1.       default in making due and punctual payment of the principal of
                  the Note, or any interest accrued thereon, when and as such
                  payment shall become due and payable, whether at maturity or
                  by acceleration or otherwise if such payment is not made
                  within five (5) days of written notice received by Maker
                  specifying such default;

         2.       the failure by Maker to comply with the covenants set forth in
                  Article II of this Note; or

         3.       the sale by Maker of all or substantially all of its assets;
                  or

         4.       the filing by Maker of a petition instituting any state or
                  federal insolvency, bankruptcy, reorganization, arrangement,
                  composition, or other debtor relief proceeding or the petition
                  of or application to any tribunal for a receiver or trustee
                  for itself or for any substantial part of any of its property.



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         If an Event of Default occurs, then and in any such case Payee may
declare the outstanding principal amount of the Note to be due and payable
immediately, upon written notice to Maker and, upon any such declaration, the
outstanding principal amount of the Note, and the interest accrued thereon,
together with all costs of collection, including reasonable attorneys' fees if
collected by law or through an attorney at law, shall immediately become due and
payable.

                                   ARTICLE IV
                                     GENERAL

1.       NOTICES. Any notice or demand given hereunder by the holder hereof must
         be in writing to be effective and shall be deemed to have been given
         and received (a) when actually delivered to the address of the party to
         be notified if delivered in person, or (b) if mailed, on the earlier of
         the date actually delivered to the address of the party to be notified
         or (whether ever so delivered or not) on the third Business Day
         (hereinafter defined) after it is enclosed in an envelope, addressed to
         the party to be notified, properly stamped, sealed, and deposited in
         the United States mail, certified mail, return receipt requested. As
         used herein, "Business Day" means every day other than a Saturday,
         Sunday, or legal holiday in Dallas, Texas.

2.       RENOUNCIATION. Maker hereby renounces to any presentation of this
         promissory note and to any notice or refusal, protest or notice of
         protest and to delay of grace.

3.       BINDING ARBITRATION. The parties hereto agree that any dispute
         pertaining to this Note and the transactions contemplated hereby must
         be submitted to the American Arbitration Association in Dallas, Texas
         for binding arbitration.

         IN WITNESS WHEREOF, the undersigned have executed this Note as of the
date first above written.


MAKER:

THE UNIMARK GROUP, INC.

By:    /s/ David E. Ziegler
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Name:  David E. Ziegler
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Title: Chief Financial Officer
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