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                                                                   EXHIBIT 10.23




                                            October 1, 1997

Mr. Robert Murdoch
706 S. Union Street
Alexandria, VA  22314

Dear Bob:

This letter is to confirm our mutual understandings with respect to the terms
and conditions upon which you agree to perform certain professional consulting
services for Lafarge Corporation (hereinafter referred to as "Lafarge") with
respect to various present and future businesses of Lafarge. Your services as a
consultant with regard to such businesses will require the application of your
knowledge of the cement, aggregate and concrete businesses as well as your
intimate familiarity with Lafarge.

Consulting services means that you are to provide Lafarge with the full benefit
of your knowledge, experience, and skill with respect to all questions and
problems which Lafarge specifies with respect to its businesses and that you
are to provide Lafarge with your analysis, advice and comments.

Your consulting services as rendered under this Agreement may be made available
to Lafarge or any of its divisions or subsidiaries.

The term of this Agreement shall be for three contract years which shall
commence October 1, 1997 and shall continue thereafter until September 30, 2000
subject to termination without prior notice by reason of your death or
incapacity or inability (determined solely by Lafarge) to perform such
services.  Lafarge shall also have the right to terminate this Agreement in the
event that you accept employment or fees from any competitor of Lafarge or its
subsidiaries in connection with Lafarge's businesses without the prior written
approval of Lafarge.

Your services in a consulting capacity under this Agreement shall be performed
under the direction of John Piecuch, President and Chief Executive Officer of
Lafarge or such other person or persons designated by him.

During the term of this Agreement Lafarge will pay you compensation of $4,000
per day not to exceed $100,000 per contract year nor $300,000 in the aggregate
during the term of this Agreement. The terms "day" and "contract year" shall
have the following meanings: a "day" shall be a period of no less than 4 hours
nor more than 14 hours in a continuous 24 hour period and a "contract year"
shall be a twelve month period beginning on October 1, and running to September
30.

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Inasmuch as in the rendering of your consulting services you will require
secret and confidential information and data concerning the operations of, or
belonging to, Lafarge, its subsidiaries and any other companies with whom
Lafarge or any subsidiary has an existing or proposed business relationship,
and additional information and data will be made available to you or be
developed by you, you agree to treat all such information and data as Lafarge's
confidential property and not to divulge it to others at any time or to use it
for your private purposes or otherwise except on behalf of Lafarge, without the
prior written consent of Lafarge, unless and until such information becomes a
part of the public domain (other than as a result of a breach of this agreement
by you) or you legally acquire such information, without restriction on
disclosure, from sources other than Lafarge, its subsidiaries, associated
companies or other companies with whom Lafarge or any subsidiary has a business
relationship. This obligation on your part to keep such information and data
confidential shall continue for five (5) years beyond and after the period of
your consulting services and upon the completion or termination of your
services, and at any time Lafarge so requests, you will deliver to Lafarge all
notes, memoranda, records, drawings, sketches or other documents (including all
copies and reproductions thereof) in connection with any information you have
access to or have developed due to your services hereunder.

You will not, without Lafarge's prior written consent, during the term of this
Agreement, for your own account or as an officer, member, employee, consultant,
representative, or advisor of any other person, corporation, partnership, or
organization, engage in or contribute your knowledge of marketing, development,
manufacture research (including without limitation market as well as technical
research) or sales relating to any products, equipment, processes, the sale or
acquisition by Lafarge of any assets or businesses, material that is or was
involved in any work or services performed pursuant to this Agreement or at any
other time by you for Lafarge or any subsidiary. However, the foregoing
sentence shall not prohibit you from engaging in any work at any time following
your retirement as a director of Lafarge upon your furnishing proof
satisfactory to Lafarge that information or data acquired or learned by you
during the period of this Agreement or at any time previously which Lafarge
considers secret or confidential to Lafarge or any subsidiary will not be
involved. Nothing in this paragraph shall be construed as limiting to any
extent your continuing obligations pursuant to the preceding paragraph.

If Lafarge requires you to travel away from your usual place of residence or
business, Lafarge will reimburse you for the reasonable traveling and living
expenses actually incurred by you upon the submission by you and approval by
Lafarge of any itemized account of the travel expenses for which you seek
reimbursement. You shall submit your statement for services rendered and your
itemized account for the expenses incurred within fifteen days of the month
following any month within which you have rendered services and/or have such
expenses. Bills for such services must specify the amount charged for each
project on which such services were performed.

In performing consulting services hereunder, your status will be that of an
independent contractor and not that of an agent, employee or part time employee
and you will not be entitled to any of the benefits available to the employees
of Lafarge. You will also be responsible for the payment of all taxes
applicable to payments made by Lafarge to you. This Agreement, however, shall
not

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affect any rights which you may now have or hereafter have under any retirement
or pension plan of Lafarge or any of its subsidiaries or affiliates.

You agree to disclose to Lafarge only such information as you are legally free
to disclose and agree that Lafarge shall have the right without any payment to
you in addition to that set forth above to freely use any and all information
disclosed by you to Lafarge.

You agree that any and all inventions, discoveries, whether or not patentable,
which (i) you conceive and/or make within the period of your consulting
services to Lafarge which are related to any question or problem with respect
to which your consulting services are utilized under this Agreement; or (ii) in
any way are based upon or embody any confidential or secret information or data
acquired directly or indirectly from Lafarge, its subsidiaries or associated
companies or which is developed by you as a result of the performance of
services pursuant to this Agreement shall be the sole and exclusive property of
Lafarge and you will, upon request by Lafarge, promptly execute any and all
applications, assignments or other instruments which Lafarge shall deem
necessary or useful in order to apply for, obtain and enforce both domestic and
foreign letters patent and/or in order to assign and convey to Lafarge the sole
and exclusive right, title and interest in and to said inventions, discoveries,
patents, applications and patents thereon. Lafarge agrees that it shall bear
the cost of preparation of all such patent applications and assignments and the
cost of prosecution of all such patent applications.

As used in this Agreement the term "subsidiary" shall mean any corporation,
partnership, joint venture or other type of business organization or
arrangement in which Lafarge now or hereafter, directly or indirectly, controls
or owns at least a 50% interest.

This Agreement shall be binding and inure to the benefit of the parties hereto
and, except as regards personal services, shall be binding upon and inure to
the benefit of the successors, heirs and legal representatives of the parties.
This Agreement shall be interpreted and construed under the laws of the
Commonwealth of Virginia.

If the foregoing terms and conditions are acceptable to you please indicate
your agreement by executing this letter in duplicate at the place indicated
below, whereupon this letter shall constitute the Agreement between you and
Lafarge with respect to your consulting services.

                                           Very truly yours,

                                           LAFARGE CORPORATION

                                           By:
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Accepted and Agreed to this __ day of _____, 1997:



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Robert W. Murdoch