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                                                                   EXHIBIT 10(r)

                              EMPLOYMENT AGREEMENT


         THIS EMPLOYMENT AGREEMENT, effective as of the 1st day of December,
1998 (the "Agreement"), by and between UNITED STATES LIME & MINERALS, INC., a
Texas corporation (herein, together with its successors and permitted assigns,
"Employer"), and HERBERT G. A. WILSON ("Employee").

                              W I T N E S S E T H

         WHEREAS, Employer desires to employ Employee, and Employee desires to
be so employed, on the terms and conditions hereinafter set forth;

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants herein contained, Employer and Employee hereby agree as follows:

         1.  Employment.

             (a) Employer hereby employs Employee to serve, subject to the
supervision and control of Employer's Board of Directors (the "Board"), as
Employer's President and Chief Executive Officer ("CEO"), and to undertake and
discharge, in accordance with the

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terms and conditions of this Agreement, such duties, functions, and
responsibilities for Employer and its subsidiaries as are from time to time
assigned to Employee by the Board.

             (b) Employer hereby agrees to use its best efforts to cause the
Board to appoint Employee as a director of Employer ("Director") effective
December 1, 1998, and there after to use its best efforts to cause the Board to
nominate, and the shareholders of Employer to elect, Employee as a Director at
each successive annual meeting of shareholders of Employer for so long as
Employee serves as CEO. Employer hereby also agrees to use its best efforts to
cause the Board to name Employee to the Executive Committee of the Board for so
long as Employee serves as a Director and CEO.

         2.  Term; Termination of Employment.

             (a) Employee's employment under this Agreement shall commence as
of December 1, 1998, or as soon thereafter as practicable, and shall continue
until December 31, 2003, and for successive one-year periods thereafter (the
"Employment Term"), unless either Employee or Employer gives at least
one-year's prior written notice of intent not to renew the Employment Term, or
Employee's employment is terminated earlier by Employee or Employer as
hereinafter provided. Immediately upon termination of Employee's employment
hereunder for any reason (other than death), Employee hereby agrees to resign
as a Director and as a director, officer, employee, and agent of each of
Employer's subsidiaries.


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             (b) Employee may terminate his employment under this Agreement at
any time, by giving at least three (3) months' prior written notice of such
termination to Employer. In the event that Employee terminates his employment
under this Agreement prior to or later than nine (9) months after a Change in
Control (as defined below), Employee shall be entitled to no Severance Payments
(as defined below). In the event that Employee terminates his employment under
this Agreement within nine (9) months after a Change in Control, Employee shall
be entitled to Severance Payments in the amount and under the circumstances set
forth in subsection 2(f) below.

             (c) Employer may terminate Employee's employment under this
Agreement at any time, for any reason or for no reason, immediately by giving
written notice to Employee. In the event that Employer terminates Employee's
employment under this Agreement for Cause (as defined below), Employee shall be
entitled to no Severance Payments. In the event that Employer terminates
Employee's employment under this Agreement without Cause, Employee shall be
entitled to Severance Payments in the amount and under the circumstances set
forth in subsection 2(f). For purposes of this Agreement, "Cause" shall be
deemed to exist if (1) Employee commits fraud, theft, larceny, or any other
crime (other than minor misdemeanors); (2) Employee fails or refuses to obey
lawful instructions of the Board or of any committee thereof, or commits any
willful misconduct or disloyalty; (3) Employee is guilty of habitual
insobriety, habitual inattention to his duties, functions, or responsibilities,
or repeated negligence in the performance of his duties, functions, or
responsibilities; or (4) Employee otherwise commits a material breach of this
Agreement.


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             (d) Employee's employment under this Agreement shall terminate
automatically upon the death or disability of Employee, or upon the expiration
of the Employment Term after Employee or Employer has given the notice of
non-renewal provided for in subsection 2(a). For purposes of this subsection
2(d), Employee shall be deemed to be disabled when he is deemed disabled under
Employer's disability policy for executive officers as in effect at that time.
In the event that Employee's employment under this Agreement terminates due to
death, disability, or non-renewal of the Employment Term, Employee shall be
entitled to no Severance Payments.

             (e) Upon any termination of Employee's employment under this
Agreement, other than a termination of Employee's employment by Employer
without Cause pursuant to subsection 2(c) or a termination by Employee within
nine (9) months after a Change in Control pursuant to subsection 2(b),
Employee, his personal representatives, or his estate, as the case may be,
shall be entitled to receive only the Base Salary (defined below) and Benefits
(defined below) paid or provided to Employee hereunder in respect of Employee's
service through the date of such termination and no other compensation.

             (f) (1) In the event that Employer terminates Employee's
employment under this Agreement without Cause pursuant to subsection 2(c), or
Employee terminates his employment under this Agreement within nine (9) months
after a Change in Control pursuant to subsection 2(b), Employee shall be
entitled to receive the Base Salary and Benefits paid or provided to Employee
hereunder in respect of Employee's service through the date of such termi-


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nation and, in addition, shall be entitled to receive severance payments (the
"Severance Pay ments") in the amount and under the circumstances set forth in
this subsection 2(f). Except in the case of a Change in Control as provided in
paragraph 2(f)(3), the Severance Payments shall consist of a continuation of
Employee's annual Base Salary and Benefits in effect on the date of
termination, paid and provided on the same periodic and other bases as provided
for in subsections 3(a) and (b) below, as if Executive's employment hereunder
were continuing. In the case of a Change in Control after which Employee elects
to receive his Severance Payments in a lump-sum as provided in paragraph
2(f)(3), the Severance Payments shall be paid in a lump-sum as provided
therein, calculated based upon Employer's out-of-pocket costs to provide the
Base Salary and Benefits, with no discounting for present value, no tax
gross-up or discount, and no effort to pay for or otherwise provide comparable
Benefits to Employee.

                 (2) In the event that Employer terminates Employee's
employment under this Agreement without Cause pursuant to subsection 2(c) prior
to a Change in Control or after two (2) years after a Change in Control,
Employee shall be entitled to Severance Payments equal to his then-current
annual Base Salary and Benefits for one (1) year.

                 (3) In the event that Employer terminates Employee's
employment under this Agreement without Cause pursuant to subsection 2(c) at
any time within two (2) years after a Change in Control, or Employee terminates
his employment under this Agreement pursuant to subsection 2(b) at any time
within nine (9) months after a Change in Control, then, notwithstanding
anything to the contrary contained in this Agreement, Employee shall be
entitled


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to Severance Payments equal to his then-current annual Base Salary and Benefits
for the greater of the number of full and partial years remaining between the
date of termination of employment and the end of the two-year period following
the Change in Control, or one (1) year. In the case of Severance Payments
related to a termination of employment after a Change in Control, or Severance
Payments related to a termination of employment before a Change in Control
which Severance Payments continue after a Change in Control, the Severance
Payments, or any remaining portion thereof, shall, at the election of Employee,
be payable in a lump sum, net of withholding for all applicable taxes and other
amounts which may be properly withheld, within thirty (30) calendar days
following such election. For purposes of this Agreement, a "Change in Control"
shall be deemed to occur if, but only if, (a) Inberdon Enterprises, Ltd.
("Inberdon ") and its affiliates and associates, on a collective basis, cease
to beneficially own, directly or indirectly, at least twenty percent (20%) of
the then-outstanding common stock of Employer, or (b) the current shareholders
of Inberdon and their affiliates and associates, on a collective basis, cease
to beneficially own, directly or indirectly, at least fifty percent (50%) of
the then-outstanding common stock of Inberdon.

                 (4) Employee acknowledges and agrees that the Severance Pay
ments provided for herein shall be in full and total satisfaction and
settlement of any and all claims, suits, demands, judgments, actions, and
causes of action, of whatever nature, which at the time of such termination
Employee then has or may have against Employer or any affiliate, subsidiary,
Director, officer, employee, agent, or shareholder of Employer or of any of its
subsidiaries, arising by virtue of any thing whatsoever, including without
limitation claims based 


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upon this Agreement, claims based upon other agreements, claims based upon
quasi-contract, claims sounding in tort, employment discrimination claims,
claims under the Employee Retirement Income Security Act of 1974, and claims
under any other federal, state, or local statute, regulation, or common law.
Employee and Employer further agree that, except in the case of a termination
of Employee's employment under this Agreement after a Change in Control
pursuant to paragraph 2(f)(3), prior to payment by Employer of any Severance
Payment or Payments Employee and Employer shall each execute and deliver
irrevocable mutual general releases of Employer and all affiliates,
subsidiaries, Directors, officers, employees, agents, and shareholders of
Employer and of all of its subsidiaries, and of Employee and his heirs and
executors, and releasing Employer, Employee, and such persons from all such
claims, in form and content reasonably acceptable to Employer, Employee, and
their respective counsel.

         3.  Compensation.

             (a) In consideration of the services to be rendered by Employee
under this Agreement, Employer shall pay Employee a salary (the "Base Salary")
at an annual rate of at least U.S. $220,000 per annum. During the fourth (4th)
quarter of each calendar year, commencing with fourth (4th) quarter 1999, the
Board or the Compensation Committee of the Board shall review and, if
appropriate, adjust the Base Salary, effective on January 1 of the next
succeeding year, and determine the amount of any bonus that Employee may be
awarded with respect to the then-current year. The Base Salary shall be payable
on a periodic basis, in arrears, in accordance with Employer's customary
payroll practices for its executives from time to time,


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net of withholding for all applicable taxes and other amounts which may be
properly withheld. Employee's bonus, if any, shall be paid within the first
(1st) quarter of the next succeeding year.

             (b) During the course of his employment under this Agreement,
Employee shall be entitled to participate in all employee health insurance,
life insurance, sick leave, long-term disability, and other fringe benefit
programs of Employer, to the extent and on the same terms and conditions
(subject, however, to the terms and conditions of any such programs) as from
time to time are accorded other employees serving as executive officers of
Employer (the "Benefits"). In lieu of Employer health insurance, Employee may
elect to have Employer pay Employee in cash, without any tax gross-up or other
adjustments, an amount equal to the costs to Employee of health insurance
benefits pursuant to the Ontario Hospital Insurance Plan (in which case, such
costs shall be considered within the definition of Benefits for purposes of
this Agreement).

             (c) Employee shall also be entitled to at least five (5) weeks'
paid vacation each calendar year, commencing with 1999, at times to be mutually
agreed upon between Employee and the Executive Committee of the Board. In
addition, Employer shall provide to Employee in Texas the use of a late model
motor vehicle suitable to Employee's executive position (Ford Crown Victoria or
comparable) and shall pay the reasonable costs of maintaining and operating
such vehicle pursuant to the customary practices of Employer. Such vehicle
shall promptly be returned to Employer, in the same condition as provided to
Employee, reasonable wear and tear excepted, upon the termination of Employee's
employment for any reason. Lastly,


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Employer shall also reimburse Employee for the following reasonable expenses
incurred by Employee in entering into this Agreement and commencing employment
in Dallas, Texas hereunder: legal fees, not to exceed U.S. $5,000, expenses of
selling his current home and moving household and personal items to the Dallas,
Texas area, not to exceed U.S. $35,000, and travel to and from and temporary
housing expenses in the Dallas, Texas area, incurred prior to Employee's move,
subject to mutual agreement between Employee and the Executive Committee of the
Board.

             (d) Employer hereby agrees to use its best efforts to cause the
Compensation Committee of the Board to grant to Employee, from time to time,
stock options under the Employer's 1992 Stock Option Plan (the "Plan").
Employer shall also use its best efforts to cause the Board and the
shareholders of Employer to increase the number of shares reserved for options
for key employees of Employer by approving and adopting, at Employer's 1999
Annual Meeting of Shareholders, either an amendment to the Plan to increase the
number of shares authorized for issuance under the Plan, or a new plan
providing for the grant of stock options. All such options shall be subject to
and governed by all of the terms and conditions of the Plan or of the new plan.

             (e) Employer shall reimburse Employee for expenses reasonably paid
or incurred by Employee in connection with the performance of his duties,
functions, and responsibilities under this Agreement, provided that Employee
shall document all such expenses in accordance with Employer's procedures in
effect from time to time.


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             (f) In respect of Employee's employment under this Agreement,
Employer shall maintain directors' and officers' liability insurance having
coverage limits at least as high as presently being maintained by Employer if
the same shall be reasonably available in the judgment of the Board.

         4.  Confidential Information. Employee hereby agrees that he shall not,
during his employment under this Agreement or at any time thereafter, furnish,
disclose, or reveal to any third party, firm, or person (except in the course
of, and only to the extent required for, the proper performance of his duties,
functions, and responsibilities hereunder), nor use or appropriate to his own
personal use or benefit or permit any third party, firm, or other person to use
or benefit from, any information of any kind or character related in any manner
to Employer or its affiliates or subsidiaries, including without limitation
information with respect to it or their financial condition, products,
businesses, operations, plans, employees, customers, suppliers, vendors, or
prospective employees, customers, suppliers, or vendors, whether or not
acquired, learned, obtained, or developed by Employee alone or in conjunction
with others ("Confidential Information"). Upon the termination of his
employment under this Agreement for any reason, Employee shall promptly return
to Employer all papers, documents, films, blueprints, drawings, magnetic tapes,
diskettes, and other storage media (of any kind) in his possession either
containing or reflecting Confidential Information, or otherwise relating to
Employer or any of its affiliates or subsidiaries, and shall not retain copies
thereof.


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         5.  Covenant Not To Compete; No Raid or Solicitation.

             (a) Employee agrees that, without the prior written consent of
Employer, he shall not, during his employment under this Agreement, and for one
(1) year following Employee's termination of his employment pursuant to
subsection 2(b) other than within nine (9) months after a Change in Control,
for six (6) months following the expiration of the Employment Term as a result
of Employee's notice of non-renewal given pursuant to subsection 2(a), for six
(6) months following Employer's termination of Employee's employment pursuant
to subsection 2(c) for Cause, for three (3) months following Employee's
termination of his employment pursuant to subsection 2(b) within nine (9)
months after a Change in Control, and for three (3) months following Employer's
termination of Employee's employment pursuant to subsection 2(c) without Cause
(collectively, the "Noncompetition Period"), engage or participate, directly or
indirectly, whether as an owner, partner, limited partner, member, director,
officer, employee, agent, consultant, or representative, in any business or
other enterprise competing, directly or indirectly, with Employer or any of its
affiliates or subsidiaries, whether now existing or hereafter created or
acquired (all the foregoing being collectively referred to herein as the
"Companies"), within the Noncompetition Areas (as defined below). A business or
other enterprise shall be deemed to be "competing" with the Companies if,
within any Noncompetition Area, it conducts (1) any line of business which the
Companies, or any of them, then conducts or has conducted within such
Noncompetition Area at any time within the one (1) year preceding the date of
termination of Employee's employment; and (2) any line of business which the
Companies, or any of them, plans, as of the date of termination of Employee's


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employment, to enter within such Noncompetition Area within the one-year period
following the termination of Employee's employment. For purposes of this
Agreement, the term "Noncompetition Areas" shall mean all those geographic
areas where the Companies, or any of them, is doing business or competing for
business at the date of termination of Employee's employment for any reason.
For purposes of this subsection 5(a), a business enterprise shall be deemed to
be conducting "business" within the Noncompetition Areas if it maintains
manufacturing, production, quarrying, sales, or distribution facilities within
the Noncompetition Areas, or solicits or services customers located within such
Noncompetition Areas. Notwithstanding anything to the contrary contained in
this subsec tion 5(a), the described restrictions on Employee's activities
shall not be deemed to include Employee's direct or indirect beneficial
ownership of any equity securities in a publicly-traded business or other
entity, which securities do not constitute more than two percent (2%) of the
relevant class of equity security issued and outstanding, or give Employee
"control" (as such term is used in the Securities Act of 1933 and the rules and
regulations promulgated thereunder) of such entity.

             (b) During the Noncompetitive Period, Employee shall also not,
either alone or with or on behalf of any third party, firm, or other person,
solicit, induce, or influence any third party, firm, or other person to (1)
solicit, divert, take away, or induce customers (wher ever located) of any of
the Companies to avail themselves of the services or products of others which
are competitive with those of any of the Companies, or sell or furnish or seek
to sell or furnish such services or products to such customers; or (2) solicit,
direct, take away, or induce any employee of any of the Companies to leave the
employ of the Companies, or hire or employ


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or seek to hire or employ any person who, at any time within six (6) months
preceding such action, was an employee of any of the Companies. For purposes of
this subsection 5(b), the term "customers" shall include any and all
individuals, business organizations and entities, and governmental agencies, no
matter how organized and regardless of whether they are organized for profit or
not, with which any of the Companies has or had agreements, contracts, or
arrangements, to which any of the Companies has sold any product or provided
any service, or with which any of the Companies has conducted business
negotiations, in each such case at any time within three (3) years prior to the
termination of Employee's employment under this Agreement.

             (c) In the event that any court of competent jurisdiction shall
determine that any restriction on Employee contained in this Section 5 is
illegal, invalid, or unenforceable by reason of the nature, scope, temporal
period, or geographic area of such restriction, or for any other reason, the
parties agree that such restriction shall be modified and reformed to the
minimum extent necessary so that such restriction, as so modified and reformed,
shall be legal, valid, and enforceable in such jurisdiction. In such event,
such restriction as so modified and reformed shall continue in effect in such
jurisdiction and such restriction, as existing prior to such modification and
reformation, shall continue in full force and effect in all other
jurisdictions. It is the intention of the parties that all restrictions on
Employee contained herein shall be enforceable for the benefit of Employer to
the maximum possible extent.


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         6.  Enforcement.

             (a) Employee recognizes and agrees that, in the event of a breach
of any of the provisions of Section 4 or 5 by Employee, Employer may suffer
irreparable harm and not have an adequate remedy at law. Accordingly, Employee
hereby agrees that, in the event of a breach or threatened breach by Employee
of any of the provisions contained in such Sections, Employer shall be
entitled, in addition to all other remedies which may be available to Employer,
to equitable relief, including without limitation enforcement of such provision
by temporary restraining order, preliminary and permanent injunction, and
decree of specific performance.

             (b) Except as set forth in subsection 6(a), any controversy or
claim arising out of or relating to this Agreement, or any breach thereof,
shall be settled by binding arbitration in the city in which Employer's
principal executive offices are located in accordance with the Commercial
Arbitration Rules of the American Arbitration Association, and judgment upon
the award rendered by the arbitrator(s) may be entered in any court having
jurisdiction thereof. The parties hereby agree to be bound by the decision of
the arbitrator(s).

         7.  Governing Law. This Agreement and the employment relationship
between Employer and Employee hereunder shall be governed by and construed and
enforced in accordance with the laws of the State of Texas, without regard to
the conflicts of law rules thereof.


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         8.  Severability. If any provision of this Agreement is held to be
illegal, invalid, or unenforceable (and, with respect to provisions contained
in Section 5, cannot be modified and reformed pursuant to subsection 5(c) such
that such provision is thereafter legal, valid, and enforceable), such
provision shall be severed and stricken from this Agreement, and in all other
respects this Agreement shall remain in full force and effect.

         9.  Only Agreement; Amendments. This Agreement constitutes the only
agreement between Employer and Employee concerning the within subject matter,
and supersedes any and all prior oral or written communications between
Employer and Employee regarding the within subject matter. No amendment,
modification, or supplement to this Agreement shall be effective, unless it is
in writing and signed by Employer and Employee.

         10. Agreement Binding; Successors and Assigns. This Agreement has been
duly authorized on behalf of Employer by the Board. This Agreement is personal
in nature, and no party hereto shall assign or transfer this Agreement or any
of its or his respective rights or obligations hereunder without the prior
written consent of the other party hereto. This Agreement shall inure to the
benefit of and be binding upon Employer and Employee and their respective
heirs, successors, and permitted assigns.

         11. Notices. Any notice required or permitted to be given hereunder
shall be in writing and shall be delivered in person, by certified or
registered mail, return receipt requested, or by overnight courier, at the
address set forth opposite the intended recipient's name 


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below. Either party may by notice to the other party hereto change the address
of the party to whom notice is to be given. The date of notice shall be the
date delivered, if delivered in person, or the date received, if delivered by
mail or overnight courier.

         12. Waiver. No waiver by any party to this Agreement of any violation,
breach, or default shall be effective unless the same shall be in writing and
signed. No waiver by any party of any violation, breach, or default shall be
construed to constitute a waiver of, or consent to, the present or future
violation, breach, or default of the same or of any other provision hereof.

         13. No Reliance; Review by Attorney. Employee hereby acknowledges and
represents that he has had full opportunity to review financial statements and
other documents relating to Employer and to ask questions of Employer
concerning its condition, financial and otherwise, business, and prospects, but
has relied solely upon his independent analysis of Employer in deciding to
execute this Agreement, having received no representations or warranties from
Employer concerning its condition, financial or otherwise, business, or
prospects. In addition, Employee acknowledges and represents that he has had
full opportunity to review the terms and conditions of this Agreement with an
attorney, that he is executing this Agreement with full knowledge of the legal
effect thereof after advice of counsel, and that his execution of this
Agreement and the performance of his duties, functions, and responsibilities


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hereunder will not conflict with, violate, breach, or constitute a default
under any law, ordinance, or regulation or any agreement, arrangement, or
understanding to which he is bound.

         IN WITNESS WHEREOF, Employer and Employee have executed this Agreement
as of the date first set forth above.

                                        UNITED STATES LIME &
                                         MINERALS, INC.



                                        By:  /s/ EDWARD A. ODISHAW
                                             ----------------------------------
                                             Edward A.  Odishaw, Esquire
                                             Chairman of the Board of Directors

Employer's Address:

Edward A.  Odishaw, Esquire
Chairman, Unites States Lime &
  Minerals, Inc.
c/o United States Lime & Minerals, Inc.
12221 Merit Drive
Suite 500
Dallas, TX  75251

Witness:                                EMPLOYEE


/s/ GILLIAN F. NIBLETT                  /s/ HERBERT G. A. WILSON
-------------------------               ------------------------------
Gillian F. Niblett                      Herbert G. A. Wilson
Employee's Address:

Herbert G. A. Wilson
c/o United States Lime & Minerals, Inc.
12221 Merit Drive
Suite 500
Dallas, TX  75251


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