<PAGE>   1

     AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON APRIL 10, 2001

                                                REGISTRATION NO. 333-
--------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   ----------

                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                                   ----------

                             THE UNIMARK GROUP, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

<TABLE>
<S>                                                       <C>
                TEXAS                                          75-2436543
      (State or jurisdiction of                            (I.R.S. Employer
   incorporation or organization)                         Identification No.)
</TABLE>

                                124 MCMAKIN ROAD
                            BARTONVILLE, TEXAS 76226
                                 (817) 491-2992
          (Address and telephone number of principal executive offices
                        and principal place of business)

                 THE UNIMARK GROUP, INC. 1999 STOCK OPTION PLAN
                            (Full title of the plan)
                                   ----------

                                 Emilio Castillo
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                             THE UNIMARK GROUP, INC.
                                124 MCMAKIN ROAD
                            BARTONVILLE, TEXAS 76226
                                 (817) 491-2992
            (Name, address and telephone number of agent for service)

                                   ----------

                                   COPIES TO:
                               JAKES JORDAAN, ESQ.
                            JORDAAN & RILEY, P.L.L.C.
                         300 CRESCENT COURT, SUITE 1660
                               DALLAS, TEXAS 75201
                                 (214) 756-6220

<TABLE>
<CAPTION>
                         CALCULATION OF REGISTRATION FEE
========================================================================================================
                                               PROPOSED MAXIMUM    PROPOSED MAXIMUM
  TITLE OF EACH CLASS OF       AMOUNT TO BE   OFFERING PRICE PER  AGGREGATE OFFERING       AMOUNT OF
SECURITIES TO BE REGISTERED   REGISTERED (1)       SHARE (2)              PRICE (2)     REGISTRATION FEE
---------------------------   --------------  ------------------  ------------------    ----------------
<S>                                 <C>          <C>                  <C>                 <C>
Common Stock, par value             40,000       $   2.500            $100,000            $   25.00
 $.01 per share
------------------------          --------       ---------            --------            ---------
Common Stock, par value             10,000       $   2.938            $ 29,380            $    7.35
 $.01 per share
------------------------          --------       ---------            --------            ---------
Common Stock, par value             30,000       $   1.500            $ 45,000            $   11.25
$.01 per share
------------------------          --------       ---------            --------            ---------
Common Stock, par value            420,000       $   0.578            $242,760            $   60.69
 $.01 per share (3)
------------------------          --------       ---------            --------            ---------
Total                              500,000                            $417,160            $  104.29
=========================================================================================================
</TABLE>


<PAGE>   2



(1)      Consists of shares of common stock that the registrant may issue
         pursuant to options granted under The UniMark Group, Inc. 1999 Stock
         Option Plan.

(2)      Estimated solely for purposes of calculating the registration fee,
         which has been computed in accordance with Rule 457(h) under the
         Securities Act of 1933, as amended.

(3)      Estimated solely for the purposes of calculating the registration fee
         pursuant to Rule 457(h) under the Securities Act of 1933, with respect
         to shares of Common Stock issuable pursuant to stock options not yet
         granted under The UniMark Group, Inc. 1999 Stock Option Plan and are
         based on the average of high and low sales prices on March 30, 2001 of
         a share of Common Stock as reported on the Over-the-Counter Bullentin
         Board

This Registration Statement on Form S-8 is filed by The UniMark Group, Inc., a
Texas Corporation (the "Company" or the "Registrant), relating to 500,000 shares
of its common stock, par value $.01 per share (the "Common Stock") issuable to
eligible employees, officers, directors and consultants of the Company under The
UniMark Group, Inc. 1999 Stock Option Plan.










                                       2

<PAGE>   3



                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

ITEM 1.  PLAN INFORMATION*

ITEM 2.  REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION*

*    As permitted by the rules of the Securities and Exchange Commission (the
"Commission"), this Registration Statement omits the information specified in
Part I of Form S-8. The documents containing the information specified in Part I
will be delivered to the participants in The UniMark Group, Inc. 1999 Stock
Option Plan (the "Plan") as required by the Securities Act of 1933 Rule 428(b).
Such documents are not being filed as part of this Registration Statement or as
prospectuses or prospectus supplements pursuant to Rule 424.



                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         The following documents have been filed by the Registrant with the
Commission and are incorporated herein by reference:

                           (a)      The Registrant's Annual Report on Form 10-K
                                    for the fiscal year ended December 31, 2000;

                           (b)      All of the Registrant's reports filed
                                    pursuant to Section 13(a) or 15(d) of the
                                    Securities Exchange Act of 1934 since the
                                    end of the fiscal year covered by the
                                    document referred to in (a) above; and

                           (c)      The description of the Registrant's Common
                                    Stock which is contained in the Registrant's
                                    registration statement on Form 8-A filed on
                                    May 18, 1995 pursuant to Section 12(g) under
                                    the Securities Exchange Act of 1934,
                                    including any amendments or reports filed
                                    for the purpose of updating such
                                    description.

         All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14, and 15(d) of the Securities Exchange Act of 1934 prior to the
filing of a post-effective amendment, which indicates that all securities
offered have been sold or which deregisters all securities remaining unsold,
shall be deemed to be incorporated by reference in this Registration Statement
and to be a part of this Registration Statement from the date of the filing of
such documents.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not applicable.



                                       3
<PAGE>   4


ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not applicable.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         Article 2.02-1 of the Texas Business Corporation Act permits a
corporation to indemnify a person who was or is a director, officer, employee,
or agent of a corporation or who serves at the corporation's request as a
director, officer, partner, proprietor, trustee, employee, or agent of another
corporation, partnership, trust, joint venture, or other enterprise (an "outside
enterprise"), who was, is, or is threatened to be named a defendant in a legal
proceeding by virtue of such person's position in the corporation or in an
outside enterprise, but only if the person acted in good faith and reasonably
believed, in the case of conduct in the person's official capacity, that the
conduct was in or, in the case of all other conduct, that the conduct was not
opposed to the corporation's best interest, and, in the case of a criminal
proceeding, the person had no reasonable cause to believe the conduct was
unlawful. A person may be indemnified within the above limitations against
judgments, fines, settlements, and reasonable expenses actually incurred.
Generally, an officer, director, agent, or employee of a corporation or a person
who serves at the corporation's request as an officer, director, agent, or
employee of an outside enterprise may not be indemnified, however, against
judgments, fines, and settlements incurred in a proceeding in which the person
is found liable to the corporation or is found to have improperly received a
personal benefit and may not be indemnified for expenses unless, and only to the
extent that, in view of all the circumstances, the person is fairly and
reasonably entitled to indemnification for such expenses. A corporation must
indemnify a director, officer, employee, or agent against reasonable expenses
incurred in connection with a proceeding in which the person is a party because
of the person's corporate position, if the person was successful, on the merits
or otherwise, in the defense of the proceeding. Under certain circumstances, a
corporation may also advance expenses to such person.

         Article 2.02-1 of the Texas Business Corporation Act also permits a
corporation to purchase and maintain insurance or to make other arrangements on
behalf of any of the above persons against any liability asserted against and
incurred by the person in such capacity, or arising out of the person's status
as such a person, whether or not the corporation would have the powers to
indemnify the person against the liability under applicable law.

         The Company's Articles of Incorporation, as amended, provide that the
Company's directors will have no personal liability to the Company or its
shareholders for monetary damages for breach of alleged breach or the directors'
duty of care. This provision has no effect on director liability for:

                  (i)      a breach of the directors' duty of loyalty to the
                           Company or its shareholders,

                  (ii)     acts or omissions not in good faith that constitute a
                           breach of duty of a director or involving intentional
                           misconduct or knowing violations of law,

                  (iii)    approval of any transaction from which a director
                           derives an improper personal benefit, or

                  (iv)     an act or omission for which the liability of a
                           director is expressly provided by an applicable
                           statute.

In addition, the Company's Articles of Incorporation, as amended, provide that
any additional liabilities permitted to be eliminated by subsequent legislation
will automatically be eliminated without further shareholder vote, unless
additional shareholder approval is required by such legislation. Article VI of
the Company's Bylaws also provides that the Company will indemnify its
directors, officers, employees and agents



                                       4
<PAGE>   5


to the fullest extent permitted by the Texas Business Corporation Act. The
Company is generally required to indemnify its directors, officers, employees,
and agents against all judgments, fines, settlements, legal fees, and other
expenses incurred in connection with pending or threatened legal proceedings
because of the person's position with the Company or another entity that the
person serves at the Company's request, subject to certain conditions, and to
advance funds to enable them to defend against such proceedings. In addition,
the Bylaws contain certain provisions intended to facilitate receipt of such
benefits.

         Insofar as indemnification for liabilities arising under the Securities
Act of 1933 may be permitted to directors, officers or persons controlling the
registrant pursuant to the foregoing provisions, the registrant has been
informed that in the opinion of the Commission such indemnification is against
public policy as expressed in the Securities Act of 1933 and is therefore
unenforceable.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.

ITEM 8.  EXHIBITS.

<TABLE>
<CAPTION>
Exhibit                  Description
-------                  -----------
<S>      <C>
4.1      Specimen Common Share Certificate of the Registrant, filed as Exhibit
         4.1 to the Registrant's Registration Statement on Form SB-2, SEC
         Registration (No. 33-78352-D) (the "SB-2 Registration Statement"), and
         incorporated herein by reference.

4.2      The UniMark Group, Inc. 1999 Stock Option Plan filed as Exhibit I to
         the Registrants Schedule 14 A Proxy Statement Pursuant to Section 14
         (a) of the Securities and Exchange Act of 1934 dated June 9, 1999, and
         incorporated herein by reference.

4.3      Certificate of Incorporation of the Registrant, filed as Exhibit 3.1 to
         the SB-2 Registration Statement, and incorporated herein by reference.

4.4      Bylaws of the Registrant, filed as Exhibit 3.2 to the SB-2 Registration
         Statement, and incorporated herein by reference.

5.1      Opinion of Jordaan & Riley, PLLC.

24.1     Consent of Jordaan & Riley, PLLC. (included in Exhibit 5.1).

24.2     Consent of Independent Certified Public Accountants.

25.1     Power of Attorney.
</TABLE>


ITEM 9.  UNDERTAKINGS.

(a)      The undersigned registrant hereby undertakes:

         (1)      To file, during any period in which offers or sales are being
                  made, a post-effective amendment to this Registration
                  Statement:



                                       5
<PAGE>   6


         (i) To include any prospectus required by Section 10(a)(3) of the
         Securities Act of 1933;

         (ii) To reflect in the prospectus any facts or events arising after the
         effective date of the Registration Statement (or the most recent
         post-effective amendment thereof) which, individually or in the
         aggregate, represent a fundamental change in the information set forth
         in the Registration Statement; and

         (iii) To include any material information with respect to the plan of
         distribution not previously disclosed in the Registration Statement or
         any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) above do not apply
if the information required to be included in a post-effective amendment by
those paragraphs is contained in periodic reports filed by the Registrant
pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 that are
incorporated herein by reference in this Registration Statement.

         (2) That, for the purpose of determining any liability under the
         Securities Act of 1933, each such post-effective amendment shall be
         deemed to be a new registration statement relating to the securities
         offered therein, and the offering of such securities at that time shall
         be deemed to be the initial bona fide offering thereof.

         (3) To remove from registration by means of a post-effective amendment
         any of the securities being registered which remain unsold at the
         termination of the offering.

(b) The undersigned issuer hereby undertakes that, for purposes of determining
any liability under the Securities Act of 1933, each filing of the Registrant's
annual report pursuant to Section 13(a) or Section 15(d) of the Securities
Exchange Act of 1934 (and, where applicable, each filing of an employee benefit
plan's annual report pursuant to Section 15(d) of the Securities and Exchange
Act of 1934) that is incorporated by reference in the registration statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers, and controlling persons of the
Registrant pursuant to the provisions described in Item 6 of this Part II, or
otherwise, the Registrant has been advised that in the opinion of the Commission
such indemnification is against public policy as expressed in the Securities Act
of 1933 and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by the
Registrant of expenses incurred or paid by a director, officer, or controlling
person of the Registrant in the successful defense of any action, suit, or
proceeding) is asserted by such director, officer, or controlling person in
connection with the securities being registered, the Registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the Securities
Act of 1933 and will be governed by the final adjudication of such issue.



                                       6
<PAGE>   7


                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Dallas, State of Texas, on April 2, 2001.


                                           THE UNIMARK GROUP, INC.
                                           a Texas corporation



                                           By: /s/ Emilio Castillo
                                               -----------------------

                                               Emilio Castillo
                                               Chief Executive Officer

                                           By: /s/ David E. Ziegler
                                              ------------------------

                                               David E. Ziegler
                                               Chief Financial Officer




                                       7
<PAGE>   8


                                INDEX TO EXHIBITS

<TABLE>
<CAPTION>
EXHIBIT
NUMBER      DESCRIPTION
-------     -----------
<S>         <C>
  5.1       Opinion of Jordaan & Riley, PLLC.

 24.1       Consent of Jordaan & Riley, PLLC. (included in Exhibit 5.1)

 24.2       Consent of Independent Certified Public Accountants.

 25.1       Power of Attorney
</TABLE>
[{"type": "S-8", "sequence": "1", "filename": "d85942s-8.txt", "description": "FORM S-8", "secsgml_size_bytes": 19829}]
{"company-data": {"conformed-name": "UNIMARK GROUP INC", "cik": "0000922712", "assigned-sic": "2033", "irs-number": "752436543", "state-of-incorporation": "TX", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-58582", "film-number": "1598566"}, "business-address": {"street1": "UNIMARK HOUSE", "street2": "124 MCMAKIN RD", "city": "BARTONVILLE", "state": "TX", "zip": "76226", "phone": "8174912992"}}
1

     AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON APRIL 10, 2001

                                                REGISTRATION NO. 333-
--------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   ----------

                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                                   ----------

                             THE UNIMARK GROUP, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)
TEXAS                                          75-2436543
      (State or jurisdiction of                            (I.R.S. Employer
   incorporation or organization)                         Identification No.)
124 MCMAKIN ROAD
                            BARTONVILLE, TEXAS 76226
                                 (817) 491-2992
          (Address and telephone number of principal executive offices
                        and principal place of business)

                 THE UNIMARK GROUP, INC. 1999 STOCK OPTION PLAN
                            (Full title of the plan)
                                   ----------

                                 Emilio Castillo
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                             THE UNIMARK GROUP, INC.
                                124 MCMAKIN ROAD
                            BARTONVILLE, TEXAS 76226
                                 (817) 491-2992
            (Name, address and telephone number of agent for service)

                                   ----------

                                   COPIES TO:
                               JAKES JORDAAN, ESQ.
                            JORDAAN & RILEY, P.L.L.C.
                         300 CRESCENT COURT, SUITE 1660
                               DALLAS, TEXAS 75201
                                 (214) 756-6220
CALCULATION OF REGISTRATION FEE
========================================================================================================
                                               PROPOSED MAXIMUM    PROPOSED MAXIMUM
  TITLE OF EACH CLASS OF       AMOUNT TO BE   OFFERING PRICE PER  AGGREGATE OFFERING       AMOUNT OF
SECURITIES TO BE REGISTERED   REGISTERED (1)       SHARE (2)              PRICE (2)     REGISTRATION FEE
---------------------------   --------------  ------------------  ------------------    ----------------
Common Stock, par value             40,000       $   2.500            $100,000            $   25.00
 $.01 per share
------------------------          --------       ---------            --------            ---------
Common Stock, par value             10,000       $   2.938            $ 29,380            $    7.35
 $.01 per share
------------------------          --------       ---------            --------            ---------
Common Stock, par value             30,000       $   1.500            $ 45,000            $   11.25
$.01 per share
------------------------          --------       ---------            --------            ---------
Common Stock, par value            420,000       $   0.578            $242,760            $   60.69
 $.01 per share (3)
------------------------          --------       ---------            --------            ---------
Total                              500,000                            $417,160            $  104.29
=========================================================================================================
2

(1)      Consists of shares of common stock that the registrant may issue
         pursuant to options granted under The UniMark Group, Inc. 1999 Stock
         Option Plan.

(2)      Estimated solely for purposes of calculating the registration fee,
         which has been computed in accordance with Rule 457(h) under the
         Securities Act of 1933, as amended.

(3)      Estimated solely for the purposes of calculating the registration fee
         pursuant to Rule 457(h) under the Securities Act of 1933, with respect
         to shares of Common Stock issuable pursuant to stock options not yet
         granted under The UniMark Group, Inc. 1999 Stock Option Plan and are
         based on the average of high and low sales prices on March 30, 2001 of
         a share of Common Stock as reported on the Over-the-Counter Bullentin
         Board

This Registration Statement on Form S-8 is filed by The UniMark Group, Inc., a
Texas Corporation (the "Company" or the "Registrant), relating to 500,000 shares
of its common stock, par value $.01 per share (the "Common Stock") issuable to
eligible employees, officers, directors and consultants of the Company under The
UniMark Group, Inc. 1999 Stock Option Plan.

                                       2
3

                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

ITEM 1.  PLAN INFORMATION*

ITEM 2.  REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION*

*    As permitted by the rules of the Securities and Exchange Commission (the
"Commission"), this Registration Statement omits the information specified in
Part I of Form S-8. The documents containing the information specified in Part I
will be delivered to the participants in The UniMark Group, Inc. 1999 Stock
Option Plan (the "Plan") as required by the Securities Act of 1933 Rule 428(b).
Such documents are not being filed as part of this Registration Statement or as
prospectuses or prospectus supplements pursuant to Rule 424.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         The following documents have been filed by the Registrant with the
Commission and are incorporated herein by reference:

                           (a)      The Registrant's Annual Report on Form 10-K
                                    for the fiscal year ended December 31, 2000;

                           (b)      All of the Registrant's reports filed
                                    pursuant to Section 13(a) or 15(d) of the
                                    Securities Exchange Act of 1934 since the
                                    end of the fiscal year covered by the
                                    document referred to in (a) above; and

                           (c)      The description of the Registrant's Common
                                    Stock which is contained in the Registrant's
                                    registration statement on Form 8-A filed on
                                    May 18, 1995 pursuant to Section 12(g) under
                                    the Securities Exchange Act of 1934,
                                    including any amendments or reports filed
                                    for the purpose of updating such
                                    description.

         All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14, and 15(d) of the Securities Exchange Act of 1934 prior to the
filing of a post-effective amendment, which indicates that all securities
offered have been sold or which deregisters all securities remaining unsold,
shall be deemed to be incorporated by reference in this Registration Statement
and to be a part of this Registration Statement from the date of the filing of
such documents.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not applicable.

                                       3
4

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not applicable.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         Article 2.02-1 of the Texas Business Corporation Act permits a
corporation to indemnify a person who was or is a director, officer, employee,
or agent of a corporation or who serves at the corporation's request as a
director, officer, partner, proprietor, trustee, employee, or agent of another
corporation, partnership, trust, joint venture, or other enterprise (an "outside
enterprise"), who was, is, or is threatened to be named a defendant in a legal
proceeding by virtue of such person's position in the corporation or in an
outside enterprise, but only if the person acted in good faith and reasonably
believed, in the case of conduct in the person's official capacity, that the
conduct was in or, in the case of all other conduct, that the conduct was not
opposed to the corporation's best interest, and, in the case of a criminal
proceeding, the person had no reasonable cause to believe the conduct was
unlawful. A person may be indemnified within the above limitations against
judgments, fines, settlements, and reasonable expenses actually incurred.
Generally, an officer, director, agent, or employee of a corporation or a person
who serves at the corporation's request as an officer, director, agent, or
employee of an outside enterprise may not be indemnified, however, against
judgments, fines, and settlements incurred in a proceeding in which the person
is found liable to the corporation or is found to have improperly received a
personal benefit and may not be indemnified for expenses unless, and only to the
extent that, in view of all the circumstances, the person is fairly and
reasonably entitled to indemnification for such expenses. A corporation must
indemnify a director, officer, employee, or agent against reasonable expenses
incurred in connection with a proceeding in which the person is a party because
of the person's corporate position, if the person was successful, on the merits
or otherwise, in the defense of the proceeding. Under certain circumstances, a
corporation may also advance expenses to such person.

         Article 2.02-1 of the Texas Business Corporation Act also permits a
corporation to purchase and maintain insurance or to make other arrangements on
behalf of any of the above persons against any liability asserted against and
incurred by the person in such capacity, or arising out of the person's status
as such a person, whether or not the corporation would have the powers to
indemnify the person against the liability under applicable law.

         The Company's Articles of Incorporation, as amended, provide that the
Company's directors will have no personal liability to the Company or its
shareholders for monetary damages for breach of alleged breach or the directors'
duty of care. This provision has no effect on director liability for:

                  (i)      a breach of the directors' duty of loyalty to the
                           Company or its shareholders,

                  (ii)     acts or omissions not in good faith that constitute a
                           breach of duty of a director or involving intentional
                           misconduct or knowing violations of law,

                  (iii)    approval of any transaction from which a director
                           derives an improper personal benefit, or

                  (iv)     an act or omission for which the liability of a
                           director is expressly provided by an applicable
                           statute.

In addition, the Company's Articles of Incorporation, as amended, provide that
any additional liabilities permitted to be eliminated by subsequent legislation
will automatically be eliminated without further shareholder vote, unless
additional shareholder approval is required by such legislation. Article VI of
the Company's Bylaws also provides that the Company will indemnify its
directors, officers, employees and agents

                                       4
5

to the fullest extent permitted by the Texas Business Corporation Act. The
Company is generally required to indemnify its directors, officers, employees,
and agents against all judgments, fines, settlements, legal fees, and other
expenses incurred in connection with pending or threatened legal proceedings
because of the person's position with the Company or another entity that the
person serves at the Company's request, subject to certain conditions, and to
advance funds to enable them to defend against such proceedings. In addition,
the Bylaws contain certain provisions intended to facilitate receipt of such
benefits.

         Insofar as indemnification for liabilities arising under the Securities
Act of 1933 may be permitted to directors, officers or persons controlling the
registrant pursuant to the foregoing provisions, the registrant has been
informed that in the opinion of the Commission such indemnification is against
public policy as expressed in the Securities Act of 1933 and is therefore
unenforceable.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.

ITEM 8.  EXHIBITS.
Exhibit                  Description
-------                  -----------
4.1      Specimen Common Share Certificate of the Registrant, filed as Exhibit
         4.1 to the Registrant's Registration Statement on Form SB-2, SEC
         Registration (No. 33-78352-D) (the "SB-2 Registration Statement"), and
         incorporated herein by reference.

4.2      The UniMark Group, Inc. 1999 Stock Option Plan filed as Exhibit I to
         the Registrants Schedule 14 A Proxy Statement Pursuant to Section 14
         (a) of the Securities and Exchange Act of 1934 dated June 9, 1999, and
         incorporated herein by reference.

4.3      Certificate of Incorporation of the Registrant, filed as Exhibit 3.1 to
         the SB-2 Registration Statement, and incorporated herein by reference.

4.4      Bylaws of the Registrant, filed as Exhibit 3.2 to the SB-2 Registration
         Statement, and incorporated herein by reference.

5.1      Opinion of Jordaan & Riley, PLLC.

24.1     Consent of Jordaan & Riley, PLLC. (included in Exhibit 5.1).

24.2     Consent of Independent Certified Public Accountants.

25.1     Power of Attorney.
ITEM 9.  UNDERTAKINGS.

(a)      The undersigned registrant hereby undertakes:

         (1)      To file, during any period in which offers or sales are being
                  made, a post-effective amendment to this Registration
                  Statement:

                                       5
6

         (i) To include any prospectus required by Section 10(a)(3) of the
         Securities Act of 1933;

         (ii) To reflect in the prospectus any facts or events arising after the
         effective date of the Registration Statement (or the most recent
         post-effective amendment thereof) which, individually or in the
         aggregate, represent a fundamental change in the information set forth
         in the Registration Statement; and

         (iii) To include any material information with respect to the plan of
         distribution not previously disclosed in the Registration Statement or
         any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) above do not apply
if the information required to be included in a post-effective amendment by
those paragraphs is contained in periodic reports filed by the Registrant
pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 that are
incorporated herein by reference in this Registration Statement.

         (2) That, for the purpose of determining any liability under the
         Securities Act of 1933, each such post-effective amendment shall be
         deemed to be a new registration statement relating to the securities
         offered therein, and the offering of such securities at that time shall
         be deemed to be the initial bona fide offering thereof.

         (3) To remove from registration by means of a post-effective amendment
         any of the securities being registered which remain unsold at the
         termination of the offering.

(b) The undersigned issuer hereby undertakes that, for purposes of determining
any liability under the Securities Act of 1933, each filing of the Registrant's
annual report pursuant to Section 13(a) or Section 15(d) of the Securities
Exchange Act of 1934 (and, where applicable, each filing of an employee benefit
plan's annual report pursuant to Section 15(d) of the Securities and Exchange
Act of 1934) that is incorporated by reference in the registration statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers, and controlling persons of the
Registrant pursuant to the provisions described in Item 6 of this Part II, or
otherwise, the Registrant has been advised that in the opinion of the Commission
such indemnification is against public policy as expressed in the Securities Act
of 1933 and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by the
Registrant of expenses incurred or paid by a director, officer, or controlling
person of the Registrant in the successful defense of any action, suit, or
proceeding) is asserted by such director, officer, or controlling person in
connection with the securities being registered, the Registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the Securities
Act of 1933 and will be governed by the final adjudication of such issue.

                                       6
7

                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Dallas, State of Texas, on April 2, 2001.

                                           THE UNIMARK GROUP, INC.
                                           a Texas corporation

                                           By: /s/ Emilio Castillo
                                               -----------------------

                                               Emilio Castillo
                                               Chief Executive Officer

                                           By: /s/ David E. Ziegler
                                              ------------------------

                                               David E. Ziegler
                                               Chief Financial Officer

                                       7
8

                                INDEX TO EXHIBITS
EXHIBIT
NUMBER      DESCRIPTION
-------     -----------
5.1       Opinion of Jordaan & Riley, PLLC.

 24.1       Consent of Jordaan & Riley, PLLC. (included in Exhibit 5.1)

 24.2       Consent of Independent Certified Public Accountants.

 25.1       Power of Attorney