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                                                                   EXHIBIT 3 (a)
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                     RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                               CABOT CORPORATION
                    (Originally incorporated July 14, 1960)

          Pursuant to Section 245, Subchapter VIII, Chapter 1, Title 8

                                     of the

                      General Corporation Law of Delaware

        CABOT CORPORATION, a corporation organized and existing under the
General Corporation Law of the State of Delaware, by authority of its Board of
Directors set forth in a vote duly adopted on October 14, 1983, restates and
integrates its Certificate of Incorporation to read in full as herein set
forth:

        FIRST:  The name of this corporation is


                               CABOT CORPORATION


        SECOND:  Its principal office in the State of Delaware is located at
No. 100 West Tenth Street, in the City of Wilmington, County of New Castle. 
The name and address of its resident agent is The Corporation Trust Company,
No. 100 West Tenth Street, Wilmington, Delaware 19801.

        THIRD:  The nature of the business of this corporation and the objects
or purposes to be transacted, promoted and carried on by it are as follows:
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        1.   To acquire, by merger, consolidation, or otherwise, the businesses
now owned and carried on by the following corporations organized and existing
under the Laws of the Commonwealth of Massachusetts:

                (a) Godfrey L. Cabot, Inc.

                (b) Cabot Carbon Company

                (c) Cabot Shops, Inc.

                (d) Cabot Gasoline Corporation

together with all their property, rights, privileges, powers and franchises;
and to assume in connection therewith all of the debts, liabilities and duties
of the said Massachusetts corporations.

        2.  To manufacture, produce, compound, refine, buy or otherwise
acquire, to sell or otherwise dispose of, and to deal in chemicals of every
description, chemical mixtures, medicines, pharmaceutical supplies, chemical
and medicinal preparations, drugs (except as forbidden by law), and any other
chemical products in the form of raw materials or otherwise, and by-products
derived from the manufacture thereof or made therefrom, carbon black, furnace
black, dye-stuffs, cements, minerals, superphosphates, soap, fertilizers,
paints, varnishes, pigments, polishes, stains, oils, acids, alcohols, coal,
coke, coal-tar, coal-tar products and derivatives, peat, peat products, rubber,
rubber goods, synthetic rubber, butadiene, and other petrochemicals of every
description, and all oher products related to any one or more of the foregoing.


                                      
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        3.  To prospect, explore, drill for, produce and accumulate oil and
gas, liquified petroleum gas and natural gasoline; to buy, lease or otherwise
acquire, to sell, lease or otherwise dispose of, and to deal in oil, gas,
natural gasoline and any and all materials incidental to or necessary for the
production of oil, gas, natural gasoline, and all the by-products thereof, and
oil and gas rights, privileges and leases of all kinds and descriptions.

        4.  To mine, produce, manufacture, refine, handle, buy, or otherwise
acquire, and to sell or otherwise dispose of, and to deal in elements,
minerals, metals, ores, precious stones and base materials of every nature and
products using the same.

        5.  To buy, sell, manufacture, fabricate, produce and deal in steel,
iron, and other metals, metal products, and all other building materials; to
construct, maintain, work or operate, plants, mills, furnaces, factories,
engines, boilers, machinery and tools; and to carry on the business of
mechanical engineers and dealers in machinery and manufacturers of plants,
engines and other machinery, tool makers, brass founders, metal workers, boiler
makers, mill-wrights, machinists, iron and steel converters, smiths, builders,
carpenters, metallurgists, and electrical, civil, mechanical and water supply
engineers.

        6.  To conduct research, scientific or technical investigations and
experiments, development work and pilot plant work, and training and
educational programs, and to seek for and develop inventions, processes,
improvements, new or improved products, and uses for products, new or improved
manufacturing and operating techniques and methods, and wider scientific,
technical, manufacturing and operating knowledge, and to furnish, to this
corporation or to others, consulting, engineering, testing, experimental and
other services, all as may relate or be incidental to or be useful or
advantageous in or in connection with any business, operation or activity in
which this corporation is authorized to engage.



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        7.  To manage and operate, in whole or in part, and to keep the books,
accounts and records, in whole or in part, of any other corporation, firm or
entity, and to enter into contracts for the performance of such service.

        8.  To carry on any manufacturing, selling, management, service,
research or other business, operation or activity which is lawful to be carried
on by a corporation organized under the General Corporation Law of the State of
Delaware as amended, whether or not similar or related or incidental to or
useful or advantageous in or in connection with the businesses, operations and
activities referred to in the foregoing paragraphs.

        9.  To manufacture, produce, purchase, lease or otherwise acquire, to
own, operate, and process, to sell, lease or otherwise dispose of, and to deal
in all kinds of machines, machinery, plant equipment, tools, materials,
merchandise, fixtures, goods and other property of all kinds useful in or in
connection with any business or activity in which this corporation is
authorized to engage.

        10.  To explore, prospect, buy, lease or otherwise acquire, to own,
hold and operate, to sell, lease or otherwise dispose of, and to deal in lands,
mining claims, water claims, water rights, mineral rights, and any other
rights, oil wells, gas wells, oil lands, gas lands and other real property, the
rights and interest in and to real property, manufacturing plants,
laboratories, pilot plants, oil refineries, gas works and plants, including
plants for the production of coke, gasoline, and other by-products, mines,
smelters, warehouses, offices and other buildings, structures, building
equipment, pipelines, railroads, and real estate improvements, all to the
extent permitted by law and as may relate or be incidental to or be useful in
or in connection with any business or activity in which this corporation is
authorized to engage.


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        11.  To acquire, hold, use, sell, assign, lease, grant licenses under,
or otherwise dispose of, letters patent of the United States or any foreign
country, patent rights, licenses and privileges, inventions, improvements and
processes, copyrights, trademarks and trade names, relating to or useful in
connection with any business in which this corporation is authorized to engage.

        12.  To subscribe for, purchase or otherwise acquire, to hold and own,
to sell, assign, transfer or otherwise dispose of, and generally to deal in and
with, securities, and while the holder or owner thereof to have and exercise
all rights, powers and privileges of ownership, including the right to vote or
consent or give proxies or powers of attorney therefor; and to carry on any
business, operation or activity through a wholly or partly owned subsidiary.

        13.  To acquire by purchase, exchange, merger or consolidation or
otherwise all or any part of the property and assets, including the business,
good will, rights and franchises, of any corporation, association, trust, firm
or individual wherever organized, created or located, and in payment or
exchange therefor to pay cash, transfer property and issue securities to the
transferor or its security holders and to assume or become liable for any
liabilities and obligations; and to hold and operate or in any manner to
dispose of all or any part of the property and assets so acquired.

        14.  To dispose by sale, exchange, merger or consolidation or
otherwise, of all or any part of the property and assets, including the
business, good will, rights and franchises, of this corporation, to any
corporation, association, trust, firm or individual wherever organized, created
or located, for cash or property, including securities, or the assumption of
the liabilities and obligations of this corporation, and if desired, and
subject to the rights of creditors and preferred stockholders (if any), to
distribute such cash, securities or other property to the security holders of
this corporation in exchange for or in partial or complete liquidation or
redemption of their securities.

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        15.  To enter into, make and perform contracts of every kind and
description with any person, firm, association, corporation, municipality,
county, state, body politic or government or colony or dependency thereof.

        16.  To have one or more offices and to carry on all or any of
operations and businesses in any and all parts of the world.

        17.  To borrow money and obtain credit; for money borrowed or for sale
or pledge or in order to pay, evidence or secure any liability or obligation,
to execute, issue and deliver and sell, pledge or otherwise dispose of bonds,
notes, debentures or other evidences of indebtedness, secured or unsecured; to
give security for any such bonds, notes, debentures or other evidences of
indebtedness or for any purchase price, guaranty, line of credit, covenant,
fidelity or performance bond or any other liability or obligation and any
premium interest and other sums due thereon or therewith and any covenants or
obligations connected therewith; and for the foregoing purposes to mortgage or
pledge or execute an indenture of mortgage or deed of trust upon or create a
lien upon or other security title or security interest in all or any part of
the property and assets, real and personal, of this corporation, then owned or
thereafter acquired.

        18.  To lend money, credit or security to, and to guarantee or assume
any liabilities and obligations of, and to aid in any other manner any
corporation, association, trust, firm or individual wherever organized, created
or located, any of whose securities are held by this corporation or in whose
affairs or prosperity this corporation has a lawful interest, and to do all
acts and things designed to protect, improve or enhance the value of such
securities or interest.

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        19.  The directors of this corporation are authorized to make
charitable contributions as defined in the United States Internal Revenue Code,
as from time to time amended, in such amounts as the directors may determine to
be reasonable.

        20.  To do any and all acts and things in this Article Third set forth,
to the same extent as an individual might or could do, as principal, factor,
consignee, agent, contractor or otherwise, and either alone or in conjunction
or jointly with any corporation, association, trust, firm or individual; and,
in general, to do any and all acts and things and to engage in any and all
businesses whatsoever, necessary, suitable, advantageous or proper for or in
connection with or incidental to the exercise, transaction, promotion or
carrying on of any of the businesses, powers, purposes or objects in this
Article Third set forth; excepting in every case all acts, things and
businesses forbidden by law.

        21.  In this Article Third the word "securities" means, to the extent
that the context permits, stocks, shares, bonds, notes, debentures and other
evidences of interest in or indebtedness of any corporation, association, trust
or firm, and notes and other evidences or indebtedness of any individual, and
bonds, notes, debentures and other evidences of indebtedness of any country,
state, county, city, town or other governmental body or agency.

        22.  In this certificate of incorporation, unless it is otherwise
expressly provided, the statements of the businesses, objects and purposes of
this corporation shall be construed both as objects and powers, the enumeration
of specific powers shall not be held to limit or restrict in any manner the
exercise by this corporation of the general powers conferred upon corporations
by the laws of the State of Delaware, and no statement of any business, object
or purpose shall be deemed to limit or be exclusive of any other stated
business, object or purpose, but all are separate and cumulative and all may be
transacted, promoted and carried on separately or together and at any time and
from time to time.

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        FOURTH:  The total number of shares of common stock which this
corporation shall have authority to issue is eighty million shares and the par
value of each of such shares is one dollar ($1.00) amounting in the aggregate
to Eighty Million Dollars ($80,000,000).

        The total number of shares of preferred stock which this corporation
shall have authority to issue is two million shares and the par value of each
of such shares is One Dollar ($1.00) amounting in the aggregate to Two Million
Dollars ($2,000,000).  The Board of Directors may provide for the issuance of
such preferred stock in one or more series, each series to have such voting
powers, full or limited, or no voting powers, such designations, preferences
and relative participating, optional or other special rights, and such
qualifications, limitations or retrictions thereof, and to be subject to such
terms of redemption, if any, as shall be specified by the Board of Directors
and stated and expressed in the vote or votes of the Board of Directors
providing for the issue of such preferred stock.

        The holders of the common stock shall be entitled to one vote for each
share of common stock registered in their respective names on the books of this
corporation.

        The board of directors may from time to time, in connection with any
employee stock option or purchase plan, fix limitations and restrictions on the
transfer of any or all of the authorized but unissued shares of this
corporation made available for such stock option or purchase plan, such
restrictions to take effect upon the issue of such shares.  No such limitation
or restriction shall be valid unless notice thereof is given on the certificate
or certificates representing such shares.


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        No stockholder of this corporation shall by reason of his holding
shares of any class have any pre-emptive or preferential purchase or subscribe
to any shares of any class of this corporation, now or hereafter to be
authorized, or any notes, debentures, bonds, or other securities convertible
into or carrying options or warrants to purchase shares of any class, now or
hereafter to be authorized, whether or not the issue of any such shares, or such
notes, debentures, bonds or other securities would adversely affect the dividend
or voting rights of such stockholder, other than such rights, if any, as the
board of directors, in its discretion from time to time may grant, and at such
price as the board of directors in its discretion may fix; and the board of
directors may issue shares of any class of this corporation, or any notes,
debentures, bonds, or other securities convertible into or carrying options or
warrants to purchase shares of any class, without offering any such shares or
securities, either in whole or in part, to the existing stockholders of any
class.

        FIFTH:  The minimum amount of capital with which the corporation will
commence business is One Thousand Dollars ($1,000.00).

        The board of directors, without the assent of or other action by the
stockholders, may from time to time authorize the issue and sale of shares of
stock of this corporation now or hereafter authorized, for such consideration
and upon such terms as the board of directors may determine, or the board of
directors may authorize such consideration and terms to be fixed in whole or in
part by any officer or officers of this corporation.

        SIXTH:  This corporation is to have perpetual existence.

        SEVENTH:  The private property of the stockholders shall not be subject
to the payment of corporate debts to any extent whatever.


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        EIGHTH:  The following provisions are inserted for the regulation and
conduct of the affairs of this corporation, and it is expressly provided that
they are intended to be in furtherance and not in limitation or exclusion of
the powers elsewhere conferred herein or in the by-laws or conferred by law:

        (a)  Except as may be otherwise expressly required by law or by other
    provisions of this certificate of incorporation or by the by-laws, the
    board of directors shall have and may exercise, transact, manage, promote
    and carry on all of the powers, authorities, businesses, objects and
    purposes of this corporation.

        (b)  The directors who are not directors emeritus shall be divided into
    three classes of approximately equal size.  At the annual meeting to be
    held January 21, 1969, one class shall be elected to a term of three years,
    another class to a term of two years, and the third class to a term of one
    year; and at each subsequent annual election the successors to directors
    whose terms shall expire that year shall each be elected to a term of three
    years.  The directors emeritus, if any, shall be elected or appointed for
    such terms and shall have such duties not contrary to law as may from time
    to time be provided for in the by-laws.  No director need be a stockholder. 
    The election of directors need not be by ballot unless the by-laws shall so
    require.

        (c)  By-laws may be made, altered, amended or repealed by a vote of the
    stockholders or a vote of the majority of the directors then in office at
    any annual, regular, or special stockholders or directors meeting, called
    for that purpose, the notice of which shall specify the subject matter of
    the proposed new by-law or the alteration, amendment, or repeal of an
    existing by-law, or the articles to be affected thereby.  Any



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    by-law whether made, altered, amended, or repealed by the stockholders or
    directors may be repealed, amended, further amended, or reinstated, as the
    case may be, by either the  stockholders or the directors as aforesaid.

        (d)  The board of directors may at any time set apart out of any of the
    funds of this corporation available for dividends a reserve or reserves for
    any proper purpose and may at any time reduce or abolish any such reserve. 
    Any other proper reserves may also be carried.

        (e)  This corporation may purchase, hold, sell and transfer shares of
    its own capital stock, but shall not use its funds or property for the
    purchase of its own shares of capital stock when such use would cause any
    impairment of the capital of this corporation, subject always to the right
    of this corporation to reduce its capital or to redeem any preferred or
    special shares out of capital as permitted by law.  Shares of its own
    capital stock belonging to this corporation shall not be voted upon
    directly or indirectly.

        (f)  The board of directors may from time to time authorize and
    maintain bonus, profit sharing or other types of incentive or compensation
    plans or pension or retirement plans for the employees (including officers
    and directors) of this corporation or of its subsidiaries, affiliates or
    any other corporation, association, trust or firm wherever organized,
    created or located in whose affairs or prosperity this corporation has any
    lawful interest and fix the amount of the profits to be distributed or
    shared and determine the persons to participate in any such plans and the
    amounts of their respective participation or benefits.


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        (g)  The board of directors may from time to time determine whether and
    to what extent and at what times and places and under what conditions and
    regulations the accounts and books and papers of this corporation, or any
    of them, shall be open to the inspection of the stockholders, and no
    stockholder shall have any right to inspect any account, book or document
    of this corporation, except as and to the extent expressly provided by law
    with reference to the right of stockholders to examine the original or
    duplicate stock ledger, or otherwise expressly provided by law, or except
    as expressly authorized by resolution of the board of directors.

        (h)  The directors of this corporation are likely to be connected with
    other corporations, partnerships, associations or firms with which from
    time to time this corporation may have business dealings.  No contract or
    other transaction between this corporation and any other corporation,
    partnership, association or firm and no act of this corporation shall be
    affected by the fact that directors of this corporation are pecuniarily or
    otherwise interested in, or are directors, members, or officers of such
    other corporation, partnership, association or firm.  Any director
    individually, or any firm of which such director may be a member, may be a
    party to or may be pecuniarily or otherwise interested in any contract or
    transaction of this corporation, provided that the fact that he or such
    firm is so interested shall be disclosed or shall have been known to the
    board of directors or a majority thereof. Every contract, act or
    transaction which at any annual meeting of the stockholders, or at any
    special meeting of the stockholders called for the purpose, among others,
    of considering such contract, act or transaction, shall be authorized,
    approved or ratified by vote of the holders of a majority of the shares of
    the capital stock of this corporation present in person or represented by
    proxy at such meeting



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    (provided that a quorum of stockholders be there present or represented by
    proxy) shall be as valid and binding upon this corporation and upon all its
    stockholders as though such a contract, act or transaction had been
    expressly authorized, approved and ratified by every stockholder of this
    corporation.

                (i)  No person shall be liable to this corporation for any loss
    or damage suffered by it on account of any action taken or omitted to be
    taken by him in good faith as a director, member of a directors' committee
    or officer of this corporation, if such person exercised or used the same
    degree of care and skill as a prudent man would have exercised or used
    under the circumstances in the conduct of his own affairs.  Without
    limitation of the foregoing, any such person shall be deemed to have
    exercised or used such degree of care and skill if he took or omitted to
    take such action in reliance in good faith upon advice of counsel for this
    corporation, or the books of account or other records of this corporation,
    or reports or information made or furnished to this corporation by any
    official, accountant, engineer, agent, or employee of this corporation, or
    by any independent public accountant or auditor, counsel, engineer,
    appraiser or other expert retained or employed by this corporation and
    selected with reasonable care by the board of directors, by any such
    committee or by any authorized officer of this corporation.

        (j)  The Company shall indemnify any person who was or is 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 (and whether or not by or in the right of the corporation) by
    reason of the fact that he is or was a director, officer, employee or agent
    of the Company, or is or was serving at the request of the Company as a
    director, officer, employee or agent of another company,


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    partnership, joint venture, trust or other enterprise, against expenses
    (including attorneys' fees), judgments, fines and amounts paid in
    settlement actually and reasonably incurred by him in connection with such
    action, suit or proceeding, to the extent and under the circumstances
    permitted by the General Corporation Law of The State of Delaware as
    amended from time to time.  Such indemnification (unless ordered by a
    court) shall be made as authorized in a specific case upon a determination
    that indemnification of the director, officer, employee or agent is
    proper in the circumstances because he has met the applicable standards of
    conduct set forth in the General Corporation Law of the State of Delaware. 
    Such determination shall be made (1) by the Board of Directors by a
    majority vote of a quorum consisting of directors who were not parties to
    such action, suit or proceeding, or (2) if such quorum is not obtainable,
    or even if obtainable a quorum of disinterested directors so directs, by
    independent legal counsel in a written opinion, or (3) by the stockholders. 
    The foregoing right of indemnification shall not be deemed exclusive of any
    other rights to which those seeking indemnification may be entitled under
    any by-law, agreement, vote of stockholders or disinterested directors or
    otherwise, and shall continue as to a person who has ceased to be a
    director, officer, employee or agent and shall inure to the benefit of the
    heirs, executors and administrators of such a person.

        NINTH:  Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof, or on the
application of any receiver or receivers appointed for this corporation under
the provisions of section 291 of Title 8 of the Delaware Code or on the


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application of trustees in dissolution or of any receiver or receivers
appointed for this corporation under the provisions of section 279 of Title 8
of the Delaware Code order a meeting of the creditors or class of creditors,
and/or of the stockholders or class of stockholders of this corporation, as the
case may be, to be summoned in such manner as the said court directs.  If
a majority in number representing three-fourths in value of the creditors or
class of creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all of the creditors or class of creditors, and/or on all the
stockholders or class of stockholders of this corporation, as the case may be,
and also on this corporation.

        TENTH:  This corporation reserves the right to amend, alter, change or
repeal any provision contained in this certificate of incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

        ELEVENTH:  The directors may be paid their expenses, if any, of
attendance at each meeting of the board of directors and may be paid a fixed
sum for attendance at each meeting of the board of directors or a stated salary
as director.  No such payment shall preclude any director from serving this
corporation in any other capacity and receiving compensation therefor.  Members
of special or standing committees may be allowed like compensation for
attending committee meetings.




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        This Restated Certificate of Incorporation restates and integrates the
corporation's Certificate of Incorporation as heretofore amended by
Certificates of Amendment as filed with the Secretary of State of the State of
Delaware on May 7, 1968, January 21, 1969, March 8, 1971, February 21, 1978 and
October 8, 1980, and eliminates certain provisions that under the General
Corporation Law of Delaware are no longer required to be included in the
Certificate of Incorporation.  Except for such provisions so eliminated, this
Restated Certificate of Incorporation does not further amend the corporation's
Certificate of Incorporation as heretofore amended and no discrepancy exists
between those provisions and the provisions of this Restated Certificate of
Incorporation.

        IN WITNESS WHEREOF,  CABOT CORPORATION has caused this Restated
Certificate of Incorporation to be duly executed this 14th day of October, 1983
by Robert A. Charpie, its President, and attested by Walter F. Greeley, its
Secretary.

                                                CABOT CORPORATION


                                                By: /S/ ROBERT A. CHARPIE
                                                   ----------------------------
ATTEST:                                            Robert A. Charpie, President


By /S/ WALTER F. GREELEY
   -----------------------------
   Walter F. Greeley, Secretary


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                            CERTIFICATE OF SECRETARY

        The undersigned, Waiter F. Greeley, hereby certifies that he is the
duly elected, Qualified and acting Secretary of CABOT CORPORATION, a
corporation organized and existing under the laws of the State of Delaware, and
that the foregoing 16 numbered pages are a true, correct and complete copy of
the Restated Certificate of Incorporation of said Corporation.

        IN WITNESS WHEREOF, I have hereunto set my hand and impressed the
corporate seal of CABOT CORPORATION on this 14th day of October, 1983.




/S/ WALTER F. GREELEY
- --------------------------
                 Secretary                               [ Corporate Seal ]
 






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