FORM OF VALHI, INC. GUARANTY
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          Valhi, Inc., a Delaware corporation ("Guarantor"), in order to induce
SIERRA PINE, a California limited partnership (the "Buyer") to enter into an
Asset Purchase Agreement dated as of January   , 1997 (the "Agreement") by and
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among Buyer and Medite Corporation, a Delaware corporation and a subsidiary of
Guarantor (the "Seller"), hereby unconditionally and irrevocably guarantees to
Buyer the full and timely performance by Seller of all of the obligations set
forth in Section 9, 10, 12 and 13 of the Agreement on Seller s part to be
performed, provided however, that Guarantor shall have no obligation to perform
any of Seller's obligations unless and until (i) Seller shall have defaulted in
the performance of such obligations and such default is continuing without cure
on the part of Seller; and (ii) Buyer shall have given Guarantor thirty (30)
day's notice of such default on the part of Seller.

          Guarantor hereby expressly waives (1) notice of acceptance of this
guaranty and (2) any other notice given to Seller in accordance with the
provisions of the Agreement on any default under the Agreement or otherwise,
except as provided in the first paragraph of this Guaranty.  Guarantor hereby
authorizes Buyer to forbear with respect to, amend, modify, enlarge, extend,
compromise and discharge any or all of the obligations of Seller under the
Agreement without notice to or consent by Guarantor.  Guarantor acknowledges and
agrees that its liability under this guaranty is joint and several with Seller
and, upon any continuing default by Seller, Buyer shall not be obligated to
first attempt enforcement against Seller but shall only be obligated to give the
notice provided in the first paragraph of this Guaranty.  Guarantor hereby
waives any and all defenses to enforcement of this guaranty, now existing or
hereafter arising, which may be available to guarantors, sureties and other
secondary parties at law or in equity.

          Guarantor represents and warrants to Buyer that (a) Guarantor is a
corporation validly existing and in good standing under the laws of the State of
Delaware; (b) all necessary corporate action has been duly taken by it to
authorize the execution, delivery and performance by it of this guaranty, (c)
this guaranty is being executed on Guarantor s behalf by a duly authorized
representative, (d) this guaranty is the legally valid and binding obligation of
Guarantor enforceable in accordance with its terms, and (e) the execution and
the delivery of this Guaranty will not (i) violate any valid constitution,
statute, regulation, rule, injunction, judgment, order, decree, ruling, charge,
or other restriction of any government, governmental agency, or court to which
the Guarantor is subject or any provision of the charter or bylaws of the
Guarantor, or (ii) conflict with, result in a breach of, constitute a default
under, result in the acceleration of, create in any party the right to
accelerate, terminate, modify, or cancel, or require any notice or consent under
any agreement, contract, lease, license, instrument, or other arrangement to
which the Guarantor is a party or by which it is bound or to which any of its
assets is subject except where the violation, conflict, breach, default,
acceleration, termination, modification, cancellation, failure to give notice or
obtain consent, would not have a material adverse effect on the financial
condition of the Guarantor taken as a whole

          Guarantor agrees to pay all reasonable costs and expenses, including
reasonable attorney fees and related costs, incurred by Buyer in enforcing
Guarantor s liability to Buyer under this guaranty whether or not a civil action
or similar proceeding (including claims and proceedings in and before the
bankruptcy court or arbitrators) is filed, prosecuted or appealed.  If an action
or proceeding is filed, prosecuted or appealed, the reasonableness of such
attorney fees shall be determined by the trial judge and if, appealed, by the
appellate court.

          This Guaranty contains the sole and entire understanding and agreement
of the undersigned and the Buyer with respect to the guarantee by the Guarantor
hereunder, and all prior negotiations, discussions, commitments,
representations, agreements and understandings heretofore had with respect
thereto are merged herein.  This Guaranty cannot be changed or terminated
orally.

          This Guaranty shall be governed by, and construed in accordance with,
the domestic laws of the State of Delaware, without giving effect to any choice
or conflict of law provision or rule (whether of the State of Delaware or any
other jurisdiction) that would cause the application of the laws of any
jurisdiction other than the State of Delaware.

          All notices, requests, demands, claims and other communications
hereunder shall be in writing and shall be given in the manner set forth in
Section17(g) of the Agreement, with all notices hereunder to Guarantor being
delivered to the address to which notices are to be given to Seller under
Section17(g) of the Agreement.

          This guaranty shall be binding upon Guarantor and its successors and
assigns, and shall inure to the benefit of and be enforceable by Buyer and its
successors and assigns.

Dated as of January    , 1997.
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                              VALHI, INC., a Delaware corporation

                              By:
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                              Name:
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