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                                                                   EXHIBIT 10(c)

                       UNITED STATES LIME & MINERALS, INC.

                 1992 STOCK OPTION PLAN, AS AMENDED AND RESTATED

         Section 1. Purpose. It is the purpose of the Plan to promote the
interests of the Company and its shareholders by attracting, retaining and
stimulating the performance of selected Employees by giving such Employees the
opportunity to acquire a proprietary interest in the Company and an increased
personal interest in its continued success and progress. Unless otherwise
specified in the option agreement, each Option granted under the Plan shall be
treated as an Incentive Stock Option.

         Section 2. Definitions. As used herein the following terms have the
following meanings:

                  (a) "Affiliate" means any parent or subsidiary corporation of
         the Company within the meaning of Section 424(e) and (f) of the Code.

                  (b) "Board" means the Board of Directors of the Company.

                  (c) "Code" means the Internal Revenue Code of 1986, as amended
         from time to time.

                  (d) "Committee" means the Stock Option Committee described in
         Section 4 hereof.



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                  (e) "Common Stock" means the $.10 par value Common Stock of
         the Company.

                  (f) "Company" means United States Lime & Minerals, Inc., a
         Texas corporation.

                  (g) "Employee" means an employee of the Company or an
         Affiliate.

                  (h) "Fair Market Value" means, unless the Committee determines
         otherwise in good faith, the closing sales price on the date in
         question (or, if there was no reported sale on such date, on the last
         preceding day on which any reported sale occurred) of the Common Stock
         reported on the National Association of Securities Dealers Automated
         Quotation System (the "Nasdaq Stock Market") or on any national stock
         exchange on which the Common Stock is then traded; or, if the Common
         Stock is not listed or admitted to trading on any such exchange and is
         not listed as a National Market security on the Nasdaq Stock Market,
         but is quoted on the Nasdaq Stock Market or any similar system then in
         use, "Fair Market Value" shall mean the average of the closing high bid
         and low asked quotations on such system for the Common Stock on the
         date in question.

                  (i) "Incentive Stock Option" means an incentive stock option
         within the meaning of Section 422(b) of the Code.

                  (j) "Option" means an option to purchase shares of Common
         Stock granted pursuant to the provisions of the Plan.

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                  (k) "Optionee" means an Employee who has been granted an
         Option under the Plan.

                  (l) "Plan" means this United States Lime & Minerals, Inc. 1992
         Stock Option Plan, as Amended and Restated.

         Section 3. Number of Shares; Per-Person Limit. Options may be granted
by the Company from time to time under the Plan to purchase an aggregate of
480,000 shares of the authorized Common Stock. If an Option expires or
terminates for any reason without having been exercised in full, the unpurchased
shares subject to such expired or terminated Option shall again be available for
purposes of the Plan. No person may be granted Options under the Plan if, after
such grant, such person will have been granted Options under the Plan that cover
in the aggregate more than 70,000 shares of Common Stock.

         Section 4. Administration of the Plan. The Plan shall be administered
by a Stock Option Committee which shall consist of two or more members of the
Board, each of whom shall be a "Non-Employee Director" within the meaning of
Rule 16b-3 under the Securities Exchange Act of 1934, as amended, and an
"outside director" within the meaning of Section 162(m) of the Code and the
regulations thereunder, or any similar or successor rule, provision or
regulation. Each member of the Committee shall be appointed by and shall serve
at the pleasure of the Board. The Board shall have the sole continuing authority
to appoint members of the Committee


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both in substitution for members previously appointed and to fill vacancies
however caused. The following provisions shall apply to the administration of
the Plan by the Committee:

                  (a) The Committee shall designate one of its members as
         Chairman and shall hold meetings at such times and places as it may
         determine. Each member of the Committee shall be notified in writing of
         the time and place of any meeting of the Committee at least two days
         prior to such meeting, provided that such notice may be waived by a
         Committee member. A majority of the members of the Committee shall
         constitute a quorum, and any action taken by a majority of the members
         of the Committee present at any duly called meeting at which a quorum
         is present (or action unanimously approved in writing) shall constitute
         action by the Committee.

                  (b) The Committee may appoint a Secretary (who need not be a
         member of the Committee) who shall keep minutes of its meetings. The
         Committee may make such rules and regulations for the conduct of its
         business as it may determine.

                  (c) No member of the Committee shall be eligible to receive an
         Option under the Plan.

                  (d) The Committee shall have full authority subject to the
         express provisions of the Plan to interpret the Plan, to provide,
         modify and rescind rules and regulations relating to it, to determine
         the terms and provisions of each Option and the form of each option
         agreement evidencing an Option granted under the Plan and to make all
         other


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         determinations and perform such actions as the Committee deems
         necessary or advisable to administer the Plan. In addition, the
         Committee shall have fall authority, subject to the express provisions
         of the Plan, to determine the Employees to whom Options shall be
         granted, the time or date of grant of each such Option, the number of
         shares subject thereto and the price at which such shares may be
         purchased. In making such determinations, the Committee may take into
         account the nature of the services rendered by the Employee, his or her
         present and potential contributions to the success of the Company's
         business and such other facts as the Committee in its discretion shall
         deem appropriate to carry out the purposes of the Plan.

                  (e) No member of the Committee shall be liable for any action
         taken or determination made in good faith with respect to the Plan or
         any Option granted hereunder.

         Section 5. Grant of Options. At any time and from time to time during
the duration of the Plan and subject to the express provisions thereof, Options
may be granted by the Committee to any Employee for such number of shares of
Common Stock as the Committee in its discretion shall deem to be in the best
interest of the Company and which will serve to further the purposes of the
Plan. The Committee, in its discretion, may designate any Option so granted as
an option that shall not be treated as an Incentive Stock Option.

         Section 6. Option Price and Payment. The purchase price per share of
Common Stock under each Option shall be determined by the Committee in its
discretion, but in no event



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shall such price be less than 100% of the Fair Market Value per share of Common
Stock at the time the Option is granted; provided, however, that the purchase
price per share of Common Stock under any Incentive Stock Option granted to an
Optionee who, at the time such Incentive Stock Option is granted, owns stock
possessing more than 10% of the total combined voting power of all classes of
stock of the Company or any Affiliate shall be at least 110% of the Fair Market
Value per share of Common Stock at the date of grant. Upon exercise of an
Option, the purchase price shall be paid in full in cash or, if and to the
extent provided for under the option agreement for such Option, in cash and/or
by delivery of shares of Common Stock already owned by the Optionee having an
aggregate Fair Market Value (determined as of the date of exercise) equal to the
purchase price, including an actual or deemed multiple series of exchanges of
such shares. The proceeds of such sale shall constitute general funds of the
Company. Upon exercise of an option, the Optionee will be required to pay to the
Company the amount of any federal, state or local taxes required by law to be
withheld in connection with such exercise.

         Section 7. Option Period and Terms of Exercise of Options. Except as
otherwise provided for herein, each Option granted under the Plan shall be
exercisable during such period commencing on or after the expiration of one year
from the date of the grant of such Option as the Committee shall determine;
provided, however, that the otherwise unexpired portion of any Option shall
expire and become null and void no later than upon the first to occur of (i) the
expiration of ten years from the date such Option was granted, (ii) the
expiration of three months from the date of the termination of the Optionee's
employment with the Company or an Affiliate for any reason other than death or
disability, or (iii) the expiration of one year from the date of the termination
of the Optionee's employment with the Company or an Affiliate by reason of


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death or disability. Anything herein to the contrary notwithstanding, the
otherwise unexpired portion of any Option granted hereunder to an Optionee shall
expire and become null and void immediately upon such Optionee's termination of
employment with the Company or an Affiliate by reason of such Optionee's fraud,
dishonesty or performance of other acts detrimental to the Company or an
Affiliate. Any Incentive Stock Option granted to an Optionee who, at the time
such Incentive Stock Option is granted, owns stock possessing more than 10% of
the total combined voting power of all classes of stock of the Company or any
Affiliate shall not be exercisable after the expiration of five years from the
date of its grant. Under the provisions of any option agreement evidencing an
Option, the Committee may limit the number of shares purchasable thereunder in
any period or periods of time during which the Option is exercisable and may
impose such other terms and conditions upon the exercise of an Option as are not
inconsistent with the terms of this Plan; provided, however, that the Committee,
in its discretion, may accelerate the exercise date of any Option to any date
following the date of grant.

         Section 8. Nontransferability of Options. An Option granted under the
Plan shall be transferable by the Optionee only by will or by the laws of
descent and distribution and shall be exercisable during the lifetime of the
Optionee only by the Optionee, or if the Optionee is legally incompetent, by the
Optionee's legal representative.

         Section 9. Termination of Employment. Transfers of employment between
the Company and any of its Affiliates shall not be considered to be a
termination of employment for the purposes of this Plan. Nothing in the Plan or
in any option agreement evidencing an Option shall confer upon any Optionee any
right to continue in the employ of the Company or any


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Affiliate or in any way interfere with the right of the Company or any Affiliate
to terminate the employment of the Optionee at any time, with or without cause.

         Section 10. Adjustments Upon Changes in Common Stock. In the event the
Company shall effect a split of Common Stock or dividend payable in Common
Stock, or in the event the outstanding Common Stock shall be combined into a
smaller number of shares, the maximum number of shares as to which Options may
be granted under the Plan and the per-person limit on Option grants set forth in
Section 3 hereof shall be decreased or increased proportionately. In the event
that, before delivery by the Company of all of the shares of Common Stock in
respect of which an Option has been granted under the Plan, the Company shall
have effected such a split, dividend or combination, the shares still subject to
such Option shall be increased or decreased proportionately and the purchase
price per share shall be decreased or increased proportionately so that the
aggregate purchase price for all of the then-optioned shares shall remain the
same as immediately prior to such split, dividend or combination.

         In the event of a reclassification of Common Stock not covered by the
foregoing, or in the event of a liquidation or reorganization (including a
merger, consolidation, spinoff or sale of assets) of the Company or an
Affiliate, the Committee shall make such adjustments, if any, as it may deem
appropriate in the number, purchase price and kind of shares covered by the
unexercised portions of Options theretofore granted under the Plan. The
provisions of this Section shall only be applicable if, and only to the extent
that, the application thereof does not conflict with any valid governmental
statute, regulation or rule.



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         Section 11. Amendment and Termination of the Plan. Subject to the right
of the Board to terminate the Plan prior thereto, the Plan shall terminate at
the expiration of ten years from April 16, 1992, the date of adoption of the
Plan by the Board. No Options may be granted after the termination of the Plan.
The Board may alter or amend the Plan but may not without the approval of the
shareholders of the Company make any alteration or amendment thereof which
operates (i) to abolish the Committee, change the qualifications of its members
or withdraw the administration of the Plan from the Committee's supervision,
(ii) to increase the total number of shares of Common Stock which may be granted
under the Plan (other than as provided in Section 10 hereof), (iii) to extend
the term of the Plan or the maximum exercise period provided in Section 7
hereof, (iv) to decrease the minimum purchase price provided in Section 6 hereof
(other than as provided in Section 10 hereof) or (v) to materially modify the
requirements as to eligibility for participation in the Plan.

         No termination or amendment of the Plan shall adversely affect the
rights of an Optionee under a previously granted Option, except with the consent
of such Optionee.

         Section 12. Modification of Options. Subject to the terms and
conditions of and within the limitations of the Plan, the Committee may modify,
extend or renew outstanding Options granted under the Plan (including the
conversion of an Incentive Stock Option into a nonqualified stock option), or
accept the surrender of Options outstanding hereunder (to the extent not
theretofore exercised) and authorize the granting of new Options in substitution
therefor. Notwithstanding the foregoing, no modification of an Option shall,
without the consent of the Optionee, alter or impair any rights or obligations
under any Option theretofore granted to



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such Optionee, except as may be necessary, with respect to Incentive Stock
Options, to satisfy the requirements of Section 422(b) of the Code.

         Section 13. Requirements of Law. The granting of Options and the
issuance of Common Stock upon the exercise of an Option shall be subject to all
applicable laws, rules and regulations and to such approval by governmental
agencies as may be required.

         Section 14. Investment Letter. The Company's obligation to deliver
Common Stock with respect to an Option shall be conditioned upon the Company's
receipt from the Employee to whom such Common Stock is to be delivered of an
executed investment letter containing such representations and agreements as the
Committee may determine to be necessary or advisable in order to enable the
Company to issue and deliver such Common Stock to such Employee in compliance
with the Securities Act of 1933, as amended, and other applicable federal, state
or local securities laws or regulations.

         Section 15. Effective Date of the Plan. The Plan shall become
effective, as of the date of its adoption by the Board, when it has been duly
approved by the holders of at least a majority of the shares of Common Stock
present or represented and entitled to vote at a meeting of the shareholders of
the Company duly held in accordance with applicable law within twelve months
after the date of adoption of the Plan by the Board. If the Plan is not so
approved, the Plan shall terminate, and any Option granted hereunder shall be
null and void.

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