EXHIBIT 3.1

                             AMENDED AND RESTATED

                         CERTIFICATE OF INCORPORATION

                                     -of-

                         USS INTERMEDIATE HOLDCO, INC.


                        _______________________________

                Pursuant to Sections 242 and 245 of the General
                    Corporation Law of the State of Delaware

                        _______________________________


          USS Intermediate Holdco, Inc., hereinafter called the "Corporation", a
corporation organized and existing under the General Corporation Law of the
State of Delaware, does hereby certify that:

          FIRST: The Corporation's original Certificate of Incorporation was
filed with the Secretary of State of the State of Delaware on January 9, 1996.

          SECOND: This Amended and Restated Certificate of Incorporation
restates, integrates and amends the Certificate of Incorporation and has been
duly adopted in accordance with Sections 242 and 245 of the General Corporation
Law of the State of Delaware.

          THIRD: The text of the Certificate of Incorporation of the Corporation
is hereby amended and restated to read in its entirety as follows:


                                 ARTICLE FIRST
                                 -------------

          The name of the Corporation is USS INTERMEDIATE HOLDCO, INC.
(hereinafter sometimes called the "Corporation").


                                ARTICLE SECOND
                                --------------


          The address of the Corporation's registered office in the State of
Delaware is Corporation Trust Center, 1209 Orange Street, City of Wilmington,
County of New Castle, State of Delaware 19801. The name of its registered agent
at such address is The Corporation Trust Company.


                                 ARTICLE THIRD
                                 -------------

          The nature of the business or purposes to be conducted or promoted are
to engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of the State of Delaware.


                                 ARTICLE FOURTH
                                 --------------

          The total number of shares of stock which the Corporation shall have
authority to issue is 25,000 shares, consisting of (i) 20,000 shares of
preferred stock, par value $.01 per share ("Preferred Stock") and (ii) 5,000
shares of common stock, par value $.01 per share ("Common Stock").


                             A. PREFERRED STOCK

          Part 1.   Ranking.  The Preferred Stock shall, with respect to amounts
                    -------
payable on redemption and distributions upon the liquidation, winding-up and
dissolution of the Corporation, rank senior to all classes of common stock of
the Corporation and to each other class of capital stock or series of preferred
stock of the Corporation (the "Junior Securities"). The Corporation may not
issue any new class or series of preferred securities or other capital stock
ranking senior to or on a parity with the Preferred Stock as to dividends,
distributions,

                                       2


amounts payable on redemption and distributions upon the liquidation, winding-up
and dissolution of the Corporation without the approval of the holders of at
least 66% of the shares of the Preferred Stock then outstanding, voting or
consenting, as the case may be, separately as one class, except that without the
approval of the holders of the Preferred Stock, the Corporation may issue shares
of preferred securities or other capital stock the proceeds of which are used to
redeem or repurchase all shares of the Preferred Stock then outstanding.

          Part 2.  Dividends. The Preferred Stock shall not accrue dividends
                   ---------
prior to the Mandatory Redemption Date, following which they shall accrue
dividends at the rate of nine percent (9%) of their liquidation preference per
annum, from the Mandatory Redemption Date until the date sufficient funds are
made available for their redemption. Such dividends, if any, shall be payable in
cash on redemption.

          Part 3.  Mandatory Redemption. The Preferred Stock shall be subject
                   ---------------------
to mandatory redemption (subject to the legal availability of funds therefor) in
whole or in part at such time as USS Holdings, Inc. ("Holdings") redeems any or
all of the outstanding shares of the Series C Preferred Stock, par value $.01
per share, of Holdings ("Holdings Preferred Stock"). Upon any such redemption of
shares of Holdings Preferred Stock, the Corporation shall be required to redeem
the number of shares of Preferred Stock equal to the number of shares of
Holdings Preferred Stock so redeemed at a redemption price equal to the
redemption price paid by Holdings with respect to such redemption of Holdings
Preferred Stock (after giving effect to all applicable provisions of the Stock
Purchase Agreement). The Corporation shall be obligated to redeem Preferred
Stock only to the extent permitted under the General Corporation Law of the
State of Delaware.

                                       3


          Part 4.  Liquidation. Upon any voluntary or involuntary liquidation,
                   -----------
dissolution or winding-up of the Corporation, the holders of the Preferred Stock
shall be entitled to be paid out of the assets of the Corporation available for
distribution, $1,000.00 plus all accumulated and unpaid dividends from the
Mandatory Redemption Date to the dates sufficient funds are made available for
redemption (or if such event occurs prior to the Mandatory Redemption Date, the
Discounted Liquidation Preference) per share before any distribution is made on
any Junior Securities, including, without limitation, common stock of the
Corporation.  After payment of the full amount of the liquidation preference to
which they are entitled, the holders of the Preferred Stock will not be entitled
to any further participation in any distribution of assets of the Corporation.
However, neither the sale, conveyance, exchange or transfer (for cash, shares of
stock, securities or other consideration) of all or substantially all of the
property or assets of the Corporation nor the consolidation or merger of the
Corporation with or into one or more corporations shall be deemed to be a
liquidation, dissolution or winding-up of the Corporation.


                               B. COMMON STOCK

          Part 1.    Voting Rights.
                     -------------

          1A.  Generally. Except as specifically required under the General
               ---------
Corporation Law of the State of Delaware, the holders of Common Stock will be
entitled to one vote per share and shall vote as one class on all matters to be
voted on by the Corporation's stockholders.

          1B.  Election of Directors. The number of directors which shall
               ---------------------
constitute the Board of Directors shall not be less than three nor more than
nine which exact number shall be established in the By-laws of the Corporation
and shall initially be three.

                                       4


          Part 2.  Dividends. When and as dividends are declared thereon, the
                   ---------
holders of Common Stock then outstanding shall be entitled to share equally and
ratably, on a share for share basis, in such dividends.

          Part 3.  Liquidation. After any payments required to be made to the
                   -----------
holders of the Preferred Stock then outstanding, the holders of Common Stock
then outstanding shall be entitled to receive equally and ratably, on a share-
for-share basis, all assets of the Corporation to be distributed upon any
liquidation, dissolution or winding up of the Corporation.


                             C. ISSUANCE OF STOCK

          Except as otherwise provided in this Certificate of Incorporation, the
Board of Directors shall have authority to authorize the issuance, from time to
time, without any vote or other action by the stockholders, of any or all shares
of stock of the Corporation of any class or series at any time authorized, and
any securities convertible into or exchangeable for any such shares, and any
options, rights or warrants to purchase or acquire any such shares, in each case
to such persons and on such terms (including as a dividend or distribution on or
with respect to, or in connection with a split or combination of, the
outstanding shares of stock of the same or any other class or series) as the
Board of Directors from time to time in its discretion lawfully may determine.
Shares so issued shall be fully paid stock, and the holders of such stock shall
not be liable to any further call or assessment thereon.



                                D. DEFINITIONS

For purposes of this Amended and Restated Certificate of Incorporation:

          "Closing" has the meaning ascribed thereto in the Stock Purchase
Agreement.

                                       5


          "Discounted Liquidation Preference" means the liquidation preference
discounted from the Mandatory Redemption Date to the date of determination at
the rate of 7.18% compounded annually.

          "Mandatory Redemption Date" means the tenth anniversary of the
Closing.

          "Stock Purchase Agreement" means the Stock Purchase Agreement dated as
of October 23, 1995 and amended as of January 29, 1996 between U.S. Borax Inc.
and USS Holdings, Inc., as the same may be amended from time to time.


                                 ARTICLE FIFTH
                                 -------------

          The following additional provisions are inserted for the management of
the business and for the conduct of the affairs of the Corporation, and for the
creation, definition, limitation and regulation of the powers of the
Corporation, the directors and the stockholders:

          1. Election of directors need not be by written ballot. The Board of
Directors shall have power to make, alter, amend and repeal the By-Laws of the
Corporation and to fix the compensation of directors for services in any
capacity.

          2. Any corporate action, with respect to which the vote of the
stockholders at a meeting thereof is required or permitted by any provision of
the General Corporation Law of the State of Delaware or of the Certificate of
Incorporation or the By-Laws of the Corporation, is authorized to be taken and
may be taken without that vote and meeting, and that vote and meeting may be
dispensed with, with the written consent of the holders of a majority (or, if
with respect to a particular corporate action where the General Corporation Law
of the State of Delaware or the Certificate of Incorporation or the By-Laws of
the Corporation specifies a greater percentage, by the holders of that greater
percentage) of the stock that would have been

                                       6


entitled to vote upon that action if a meeting were held. Prompt notice shall be
given to all stockholders of the taking of any corporate action pursuant to the
provisions of this paragraph 2 unless that action has been consented to in
writing by the holders of all of the stock that would have been entitled to vote
upon that action if a meeting were held.

          3. A director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived an improper
personal benefit.

          Any repeal or amendment of this Article, insofar as it would in any
way enlarge the liability of any director of the Corporation, shall be
ineffective with respect to any acts or omissions occurring prior to the date of
such repeal or amendment.


                                 ARTICLE SIXTH
                                 -------------

          The Corporation shall indemnify any person who was or is a party, or
is threatened to be made a party, to any threatened, pending or completed
action, suit or proceeding, whether civil, criminal, administrative or
investigative, including an action by or in the right of the Corporation, by
reason of the fact that he, or the person whose legal representative he is, (1)
is or was a stockholder, director, officer, employee or agent of the Corporation
(including the incorporator thereof), or (2) is or was serving at the request of
the Corporation as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise, or (3) is or
was a director, officer or employee of the

                                       7


Corporation serving at the request of the Corporation as a fiduciary of an
employee benefit plan or trust maintained for the benefit of employees of the
Corporation or employees of any such other enterprise, partnership, joint
venture, trust, or other enterprise, against judgments, fines, penalties,
amounts paid in settlement, and expenses, including attorneys' fees, actually
and reasonably incurred by him and the person whose legal representative he is,
in connection with such action, suit or proceeding, or any appeal therein, to
the fullest extent permitted by law.

          Expenses which may be indemnifiable under this Article SIXTH in
defending an action, suit or proceeding may be paid by the Corporation in
advance of the final disposition of such action, suit or proceeding as
authorized by the Board of Directors upon agreement by or on behalf of the
stockholder, director, officer, employee or agent, or his legal representative,
to repay such amount if he is later found not entitled to be indemnified by the
Corporation as authorized in this Article SIXTH.

          The Corporation shall not indemnify any stockholder, director,
officer, employee or agent against judgments, fines, amounts paid in settlement
and expenses, including attorneys' fees, to an extent greater than that
authorized by this Article SIXTH, but the Corporation may procure insurance
providing greater indemnification and may share the premium cost with any
stockholder, director, officer, employee or agent on such basis as may be agreed
upon.

                                       8


          IN WITNESS WHEREOF, the Corporation has caused this Amended and
Restated Certificate of Incorporation to be signed by Anthony J. Petrocelli, its
Vice Chairman, and attested by Donald G. Kilpatrick, its Secretary, as of the
9th day of February, 1996.

                                             USS INTERMEDIATE HOLDCO, INC.



                                             By: /s/ Richard J. Nick
                                                 -------------------
                                                 Richard J. Nick
                                                 Vice President

ATTEST:



By: /s/ Donald G. Kilpatrick
    ------------------------
    Donald G. Kilpatrick
    Secretary

                                       9