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                                                                   Exhibit 10.67

                             STOCK OPTION AGREEMENT

      This Stock Option Agreement ("Agreement") is made as of October 1, 2004,
by The UniMark Group, Inc., a Texas corporation ("UniMark" or the "Company"),
and Jakes Jordaan ("Option Holder").

                                 R E C I T A L S

      In consideration of the premises and the mutual promises herein made, and
in consideration of the covenants herein contained, the parties hereto agree as
follows:

      1.    Grant of Option. UniMark grant to the Option Holder an option (the
"Option") to purchase up to 2,104,182 shares (the "Underlying Shares") of the
Company's common stock, par value $.01 per share ("Common Stock"), at an
exercise price per share of $.40 (the "Initial Option Price"). The Option shall
be effective as of October 1, 2004 (the "Effective Date").

      2.    Vesting.

            (a)   Formula Vesting. The Option shall only be exercisable based
                  upon the Aggregate Cash Distribution Amount (as defined below)
                  to holders of the Company's equity securities in accordance
                  with the formula:

                  Vested Number of Underlying Shares = 2,104,182 x (Aggregate
                  Cash Distribution Amount/Unrecovered Capital)

                  "Aggregate Cash Distribution Amount" shall mean the aggregate
                  dollar amount of (a) any cash dividends or distribution to
                  holders outstanding shares of Common Stock, (b) any cash used
                  by the Company or its subsidiaries to repurchase shares of
                  Common Stock, and (c) any payments by the Company or its
                  subsidiaries made to persons or entities owning beneficially
                  more than 10 percent of the Company's outstanding shares of
                  Common Stock less (d) amounts (other than salary paid and
                  normal and customary employee benefits) paid to Option Holder
                  by the Company or its subsidiaries.

                  "Unrecovered Capital" shall mean $8,417,932 reduced by amounts
                  under (a), (b) and (c) under the definition of Aggregate Cash
                  Distribution Amount as and when paid or expended and increased
                  by eight percent (8%) per annum compounded quarterly
                  commencing July 1, 2004.

                  The number of shares of Common Stock for which the Option may
                  be exercised shall be cumulative, so that once the Option
                  shall become exercisable with respect to any shares of Common
                  Stock it shall continue to be exercisable for such shares
                  until expiration of termination of the Option.
                  Notwithstanding, no portion of the Underlying Shares subject
                  to the Option shall vest after July 1, 2008, in accordance
                  with the formula under this Section 2(a).

            (b)   Other Vesting. Any Underlying Shares subject to the Option
                  which have not vested on July 1, 2008, shall thereafter vest
                  immediately and the Option for such Underlying Shares shall be
                  exercisable at the Initial Option Price without any reduction
                  thereof under Section 3(a).

      3.    Adjustments.

            (a)   Adjustment for Cash Dividends. If at any time UniMark declares
                  a cash dividend or make any other distribution on its
                  outstanding shares of Common Stock, then the Initial Option
                  Price with respect to any Underlying Shares for

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                  which vesting has occurred pursuant to Section 2(a) shall be
                  reduced by the per share amount received by holders of the
                  Common Stock. Notwithstanding the foregoing, the Initial
                  Option price shall be not less than $.01 per share or the par
                  value of Common Stock if less than $.01.

            (b)   Adjustment by Stock Split, Stock Dividend, Etc. If at any time
                  UniMark increases or decreases the number of its outstanding
                  shares of Common Stock, or changes in any way the rights and
                  privileges of such shares, by means of the payment of a stock
                  dividend or the making of any other distribution on such
                  shares payable in shares of Common Stock, or through a stock
                  split or subdivision of shares, or a consolidation or
                  combination of shares, or through a reclassification or
                  recapitalization involving the stock, or other change
                  affecting the outstanding Common Stock without the Company's
                  receipt of consideration, then appropriate adjustments shall
                  be made to (i) the total amount and/or class of securities
                  subject to this Option and (ii) the Initial Option Price in
                  order to reflect such change and thereby preclude a dilution
                  or enlargement of benefits hereunder.

            (c)   Adjustments for Redemptions. The Underlying Shares represent
                  ten percent (10%) of the issued and outstanding Common Stock
                  of the Company ("Percentage Amount"). In the event the Company
                  redeems, or its subsidiaries acquire, any of the issued and
                  outstanding Common Stock for cash or other valuable
                  consideration, the number of Underlying Shares shall be
                  reduced so that it represents the Percentage Amount of the
                  Common Stock issued and outstanding following any such
                  transaction.

      4.    Change of Control. Upon (i) any transaction or series of related
transactions (including, without limitation, any reorganization, merger, or
consolidation) that will result in the holders of the outstanding voting equity
securities of UniMark immediately prior to such transaction holding less than a
majority of the voting equity securities of the surviving entity immediately
following such a transaction (a "Merger"), (ii) the sale or transfer of all or
substantially all of the assets of UniMark (an "Asset Sale"), (iii) the
dissolution or liquidation of UniMark, then immediately prior to the effective
date of such event, this Option shall be accelerated so that the Option Holder
may exercise the Option (whether or not then vested) for all the shares of
Common Stock subject to the Option as fully vested shares.

      5.    Expiration and Termination of the Option. The Option shall expire
ten (10) years from the Effective Date (the period from the Effective Date to
the expiration date is the "Option Period") or prior to such time as follows:

            (a)   If the employment of the Option Holder is terminated within
                  the Option Period for any reason other than Disability or
                  death, the Option may be exercised by the Option Holder within
                  three (3) months following the date of such termination
                  (provided that such exercise must occur within the Option
                  Period), but not thereafter. In any such case, the Option may
                  be exercised only as to the vested shares of Stock as to which
                  the Option had become exercisable on or before the date of the
                  Option Holder's termination of employment.

            (b)   If the Option Holder dies within the Option Period, while
                  employed by UniMark, the Option may be exercised by those
                  entitled to do so under his will or by the laws of descent and
                  distribution within one (1) year following his or her death
                  (provided that such exercise must occur within the Option
                  Period), but not thereafter. In any such case, the Option may
                  be exercised only as to the vested shares of Stock as to which
                  the Option had become exercisable on or before the date of the
                  Option Holder's death.

            (c)   If the Option Holder becomes disabled within the Option
                  Period, while employed by UniMark, the Option may be exercised
                  within one (1) year

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                  following his termination of employment because of disability
                  (provided that such exercise must occur within the Option
                  Period), but not thereafter. In any such case, the Option may
                  be exercised only as to the vested shares of Stock as to which
                  the Option had become exercisable on or before the date of the
                  Option Holder's termination of employment because of
                  disability.

      6.    Exercise of Option.

            (a)   Payment. Subject to compliance with the terms and conditions
                  of this Agreement and applicable securities laws, this Option
                  may be exercised, in whole or in part at any time or from time
                  to time, during the Option Period by the delivery of notice of
                  such exercise specifying the number of shares of Common Stock
                  being acquired, at the principal office of the Company,
                  together with payment, (i) in cash (by check) or by wire
                  transfer, (ii) by cancellation of any outstanding debt and/or
                  accrued interest owing by the Company to the Option Holder,
                  (iii) by exchange of the Company's securities held by the
                  Option Holder, at the fair market vale thereof, or (iv) by a
                  combination of (i), (ii) and (iii), of an amount equal to the
                  product obtained by multiplying the number of shares of Common
                  Stock being purchased upon such exercise by the then effective
                  Initial Option.

            (b)   Net Issue Exercise. In lieu of the payment methods set forth
                  in Section 6(a) above, the Option Holder may elect to exchange
                  all or some of this Option for shares of Common Stock equal to
                  the value of this Option being exchanged on the date of
                  exchange. If the Option Holder elects to exchange this Option
                  as provided in this Section 6(b), the Option Holder shall
                  tender to the Company in the notice of exercise so much of the
                  Option for the amount being exchanged, along with written
                  notice of the Option Holder's election to exchange some or all
                  of the Option, and the Company shall issue to the Option
                  Holder the number of shares of Common Stock computed using the
                  following formula:

                                    X       =        Y(A-B)
                                                     ------
                                                        A

                  Where X = the number of shares of Common Stock to be issued to
                  the Option Holder.

                  Y = the number of shares of Common Stock purchasable under the
                  amount of the Option being exchanged (as adjusted to the date
                  of such calculation).

                  A = the fair market value of one share of Common Stock.

                  B = the then effective Initial Option Price.

                  All references to an "exercise" of the Option shall include an
                  exchange pursuant to this Section 6.6(b).

      7.    Transferability. Option Holder may assign or transfer the Option his
family limited partnership and/or trust created for the benefit of his children.
The Option may be transferred by will or pursuant to the laws of descent and
shall be exercisable during the Option Holder's life only by the Option Holder,
or in the event of Disability or incapacity, by the Option Holder's guardian or
legal representative, and after the Option Holder's death, only by those
entitled to do so under the Option Holder's will or the applicable laws of
descent and distribution.

      8.    Condition to Exercise. As a condition to the exercise of all or any
portion of the Option, the Option Holder shall enter into an agreement with
Cardinal UniMark Investors, L.P., a Delaware limited

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partnership ("CUI"), containing usual and customary terms and conditions which
are commercially reasonable and under which:

            (a)   CUI shall be entitled to vote any shares of Common Stock
                  acquired upon the exercise of the Option with respect to a
                  transaction involving the Company requiring common shareholder
                  approval;

            (b)   CUI may cause the Option Holder to transfer or dispose of any
                  shares of Common Stock acquired upon exercise of the Option on
                  the same terms and conditions and for the same consideration
                  as CUI transfers all of its shares of Common Stock;

            (c)   CUI may require the Option Holder to waive any appraisal or
                  similar rights with respect to transactions described in (a)
                  or (b) above and execute such further agreements as may be
                  required to consummate such transactions.

            CUI shall be a third-party beneficiary of the provisions of this
      Section 8 and the Company shall not issue any shares of Common Stock to
      the Option Holder pursuant to this Agreement unless and until it has been
      notified in writing by CUI that the Option Holder and CUI have entered
      into the agreement contemplated herein.

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the
day and year first above written.

                                                     THE UNIMARK GROUP, INC.

                                                     By: /s/ Robert J. Bobb
                                                         ------------------
                                                         Robert J. Bobb
                                                         Its Chairman

                                                     OPTION HOLDER:

                                                         /s/ Jakes Jordaan
                                                         -----------------
                                                         Jakes Jordaan

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                              NOTICE OF ASSIGNMENT

      Pursuant to Section 7 of that certain Stock Option Agreement dated as of
October 1, 2004, by The UniMark Group, Inc. and Jakes Jordaan (the "Option
Agreement"), notice is hereby given that Jakes Jordaan has assigned and
transferred the Option (as defined in Option Agreement), effective as of
December 4, 2004, to his family's limited partnership: S4J2 Family Limited
Partners, L.L.P., a Texas limited liability partnership.

/s/ Jakes Jordaan
-----------------
Jakes Jordaan