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                                                                       Exhibit 5





                                 March 29, 1995


United States Lime & Minerals, Inc.
12221 Merit Drive
Suite 500
Dallas, Texas  75251

             Re:          Registration Statement on Form S-8 Relating to
                          the United States Lime & Minerals, Inc. 1992
                          Stock Option Plan, as Amended                 

Ladies and Gentlemen:

             We have acted as counsel to United States Lime & Minerals, Inc., a
Texas corporation (the "Company"), in connection with the preparation of a
registration statement on Form S-8 (the "Registration Statement") to be filed
with the Securities and Exchange Commission (the "Commission") under the
Securities Act of 1933, as amended (the "Securities Act"), relating to 380,000
shares of the Company's common stock (the "Registered Shares"), $.10 par value
per share (the "Common Stock"), to be offered and sold under the Company's 1992
Stock Option Plan, as amended (the "Plan").

             In connection with this opinion, we have examined the Registration
Statement, the Restated Articles of Incorporation and Composite Copy of Bylaws
of the Company, certain of the Company's corporate proceedings as reflected in
its minute books, and such other records as we have deemed relevant.  In our
examinations, we have assumed the genuineness of all signatures, the
authenticity of all documents submitted to us as originals, and the conformity
with the originals of all documents submitted to us as copies.  In addition, we
have made such other examinations of law and fact as we have deemed appropriate
in order to form a basis for the opinion hereinafter expressed.

             In our opinion, the Registered Shares that may be originally
issued by the Company in connection with the Plan will, when issued in
accordance with the terms of the Plan, be legally issued, fully paid, and
non-assessable shares of Common Stock.

             The opinion set forth above is limited to the Texas Business
Corporation Act, as amended.
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United States Lime & Minerals, Inc.
March 29, 1995
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             We hereby consent to the filing of this opinion as Exhibit 5 to
the Registration Statement.  In giving such opinion and consent, we do not
thereby admit that we are acting within the category of persons whose consent
is required under Section 7 of the Securities Act or the rules and regulations
of the Commission thereunder.

                                         Very truly yours,


                                         /s/ Morgan, Lewis & Bockius