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                                                                    EXHIBIT (4h)


            FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

                  THIS FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT
AGREEMENT, dated as of September 30, 1999 ("Amendment"), by and among Brush
Wellman Inc., an Ohio corporation ("Borrower"), the banks that are parties to
this Amendment (the "Banks"), and National City Bank, as agent for the Banks (in
that capacity, "NCB-Agent"),

                                WITNESSETH THAT:

                  WHEREAS, Borrower, the Banks and NCB-Agent entered into an
Amended and Restated Credit Agreement, dated as of December 13, 1994, as amended
by a First Amendment to Amended and Restated Credit Agreement dated December 30,
1996, by a Second Amendment to Amended and Restated Credit Agreement dated
September 2, 1997 and by a Third Amendment to Amended and Restated Credit
Agreement dated January 26, 1999 (together with all Exhibits and Schedules
thereto, the "Credit Agreement"), under which the Banks, subject to certain
conditions, agreed to lend to Borrower up to $55,000,000 from time to time in
accordance with the terms thereof; and

                  WHEREAS, the parties desire to amend the Credit Agreement as
set forth herein;

                  NOW, THEREFORE, in consideration of the premises and the
mutual covenants and agreements contained herein, the parties hereto agree as
follows:

                  1.       Effect of Amendment; Definitions.

                  The Credit Agreement shall be and hereby is amended as
provided in Section 2 hereof. Except as expressly amended in Section 2 hereof,
the Credit Agreement shall continue in full force and effect in accordance with
its respective provisions on the date hereof. As used in the Credit Agreement,
the terms "Credit Agreement", "Agreement", "this Agreement", "herein",
"hereinafter", "hereto", "hereof", and words of similar import shall, unless the
context otherwise requires, mean the Credit Agreement as amended and modified by
this Amendment.

                  2.       Amendments.

                  (A) Subsection 2A.01 of the Credit Agreement shall be amended
by deleting the same and substituting in lieu thereof the following:

                  "2A.01 AMOUNTS. The aggregate amount of the Subject
Commitments shall be fifty five million dollars ($55,000,000), but that amount
may be reduced from time to time pursuant to subsection 2A.03 and the Subject
Commitments may be terminated pursuant to Section 5B. The amount of each Bank's
Subject Commitment (subject to such reduction or termination), and the
proportion (expressed as a percentage) that it bears to all of the Subject
Commitments, is set forth opposite the Bank's name below, to-wit:

                  $15,000,000       27.275%  National City Bank
                  $10,000,000        18.18%  Fifth Third Bank, Northeastern Ohio
                  $15,000,000       27.275%  Bank One, Michigan
                  $ 5,000,000         9.09%  Firstar Bank, N.A.
                  $10,000,000        18.18%  Harris Trust and Savings Bank
                  -----------                -----------------------------------
                  $55,000,000                        Total"


                                                                          Page 1

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                  (B) Subsection 2A.04(b) of the Credit Agreement shall be
amended by deleting the table in the definition of "Applicable Rate" in the
first paragraph therein and substituting the following in lieu thereof:

<TABLE>
<CAPTION>
If the Ratio of the Companies' Funded
Indebtedness to the Companies' EBITDA is:            The Applicable Rate is:
<S>                                                  <C>
         Less than 4.25 to 1.00, but greater
         than or equal to 4.00 to 1.00                        0.45%

         Less than 4.00 to 1.00, but greater
         than or equal to 3.50 to 1.00                       0.375%

         Less than 3.50 to 1.00, but greater
         than or equal to 3.00 to 1.00                        0.30%

         Less than 3.00 to 1.00                               0.25%
</TABLE>

                  (From October 1, 1999, until changed hereunder in accordance
with the following provisions, the Applicable Rate will be 0.45% per annum.)"

                  (C) Subsection 2B.09(a) of the Credit Agreement shall be
amended by deleting the table in the definition of "Applicable Margin" in the
first paragraph therein and substituting the following in lieu thereof:

<TABLE>
<CAPTION>
If the Ratio of the Companies' Funded
Indebtedness to the Companies' EBITDA is:            The Applicable Margin is:
<S>                                                  <C>
         Less than 4.25 to 1.00, but greater
         than or equal to 4.00 to 1.00                          1.375%

         Less than 4.00 to 1.00, but greater
         than or equal to 3.50 to 1.00                          1.125%

         Less than 3.50 to 1.00, but greater
         than or equal to 3.00 to 1.00                          1.00%

         Less than 3.00 to 1.00, but greater
         than or equal to 2.50 to 1.00                          0.75%

         Less than 2.50 to 1.00                                 0.50%
</TABLE>

                  (From October 1, 1999, until changed hereunder in accordance
with the following provisions, the Applicable Rate will be 1.375% per annum.)"


                  (D) Subsection 3B.02 of the Credit Agreement shall be amended
by deleting the same and substituting in lieu thereof the following:

                  "3B.02 LEVERAGE. Borrower will not suffer or permit the
Companies' Funded Indebtedness at any time to exceed an amount equal to the
Leverage Multiplier (as


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hereinafter defined) times the Companies' EBITDA for the four consecutive fiscal
quarters most recently ended, all as determined on a consolidated basis. As used
herein, "Leverage Multiplier" means (i) from April 1, 1999, to September 30,
1999, inclusive, 4.25, (ii) from October 1, 1999, to December 31, 1999,
inclusive, 4.00, (iii) from January 1, 2000, to March 31, 2000, inclusive, 3.75,
(iv) from April 1, 2000, to June 30, 2000, inclusive, 3.50, (v) from July 1,
2000, to December 31, 2000, inclusive, 3.25, and (vi) on and after January 1,
2001, 3.00."

                  (E) Subsection 3D.01(iv) of the Credit Agreement shall be
amended by deleting the same and substituting in lieu thereof the following:

                  "(iv) any guaranty by Borrower of indebtedness of any Company
         otherwise permitted by this Agreement and any guaranty by Borrower or
         any Company of any obligations of any other Company that deals in
         precious metals under any consignment arrangement that is permitted
         under Subsection 3D.03(a),"

                  (F) Subsection 3D.03(a) of the Credit Agreement shall be
amended by deleting the same and substituting in lieu thereof the following:

                  "(a) lease any property as lessee or acquire or hold any
                  property subject to any land contract, inventory consignment
                  (except for any precious metals inventory of a Company that
                  deals in precious metals that is subject to any consignment
                  arrangement or consignment arrangements that are approved by
                  NCB-Agent, which approval will not be unreasonably withheld,
                  and only so long as the aggregate value, in United States
                  Dollars, of the precious metals subject thereto does not
                  exceed an amount greater than $75,000,000 at any time), or
                  other title retention contract,"

                  (G) Exhibits E to the Credit Agreement is hereby deleted and
Exhibit E attached to this Amendment is substituted in lieu thereof.

                  3. Substitution of Banks. Borrower and each of the Banks that
are parties to this Amendment hereby acknowledge and agree that by virtue of the
execution and delivery of this Amendment, together with appropriate assignment
agreements, and as of the date hereof (a) one-half of the Subject Commitment of
Bank One, NA has been assigned to Bank One, Michigan, formerly known as NBD
Bank, and one-half has been assigned to Firstar Bank, N.A., and (b) Firstar
Bank, N.A., will become a Bank that is a party to the Credit Agreement as
provided in Subsection 2A.01.

                  4. Representations and Warranties.

                  (A) Borrower hereby represents and warrants to the Banks and
NCB-Agent that all representations and warranties set forth in the Credit
Agreement, as amended hereby, are true and correct in all material respects, and
that this Amendment and the Subject Notes delivered in connection with this
Amendment have been executed and delivered by a duly authorized officer of
Borrower and constitute the legal, valid and binding obligation of Borrower,
enforceable against Borrower in accordance with their respective terms.

                  (B) The execution, delivery and performance by Borrower of
this Amendment and its performance of the Credit Agreement and the Subject Notes
delivered in connection with this Amendment have been authorized by all
requisite corporate action and will


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not (1) violate (a) any order of any court, or any rule, regulation or order of
any other agency of government, (b) the Articles of Incorporation, the Code of
Regulations or any other instrument of corporate governance of Borrower, or (c)
any provision of any indenture, agreement or other instrument to which Borrower
is a party, or by which Borrower or any of its properties or assets are or may
be bound; (2) be in conflict with, result in a breach of or constitute, alone or
with due notice or lapse of time or both, a default under any indenture,
agreement or other instrument referred to in (1)(c) above; or (3) result in the
creation or imposition of any lien, charge or encumbrance of any nature
whatsoever.

                  5. Miscellaneous.

                  (A) This Amendment shall be construed in accordance with and
governed by the laws of the State of Ohio, without reference to principles of
conflict of laws. Borrower agrees to pay to the Banks at the time this Amendment
is executed and delivered by the Banks an amendment fee in an aggregate amount
equal to $55,000, to be allocated pro rata among the Banks on the basis of their
respective Subject Commitments immediately after this Amendment is executed and
delivered by the Banks, and to pay on demand all costs and expenses of the Banks
and NCB-Agent, including reasonable attorneys' fees and expenses, in connection
with the preparation, execution and delivery of this Amendment.

                  (B) The execution, delivery and performance by the Banks and
NCB-Agent of this Amendment and the Subject Notes executed in connection
herewith shall not constitute, or be deemed to be or construed as, a waiver of
any right, power or remedy of the Banks or NCB-Agent, or a waiver of any
provision of the Credit Agreement. None of the provisions of this Amendment
shall constitute, or be deemed to be or construed as, a waiver of any "Default
under this Agreement" or any "Event of Default," as those terms are defined in
the Credit Agreement.

                  (C) This Amendment may be executed in two or more
counterparts, each of which shall constitute an original, but all of which, when
taken together, shall constitute but one instrument.



                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]


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                  IN WITNESS WHEREOF, the parties have caused this Amendment to
be duly executed as of the day and year first above written.

<TABLE>
<CAPTION>
<S>                                                  <C>
Address:                                             BRUSH WELLMAN INC.
         17876 St. Clair Avenue
         Cleveland, Ohio 44110
         Fax:  (216) 481-2523                        By:      /s/ Michael C. Hasychak
                                                     Title:   Treasurer and Secretary


Address:                                             NATIONAL CITY BANK,
Deliveries:                                          for itself and as Agent
         Large Corporate Division
         1900 East Ninth Street
         Cleveland, Ohio 44114-3484                  By:      /s/ Janice E. Focke
         Fax:  (216) 222-0003                        Title:   Vice President

Mail:
         Large Corporate Division, Loc. #2077
         P.O. Box 5756
         Cleveland, Ohio 44101


Address:                                             FIFTH THIRD BANK, NORTHEASTERN OHIO

         1404 East Ninth Street
         Cleveland, Ohio 44114                       By:      /s/ James P. Byrnes
         Fax:  (216) 274-5507                        Title:   Vice President


Address:                                             BANK ONE, MICHIGAN

         611 Woodward
         Detroit, Michigan 48226                     By:      /s/ Patrick F. Dunphy
         Fax:  (313) 225-1212                        Title:   Vice President


Address:                                             HARRIS TRUST AND SAVINGS BANK

         P.O. Box 755 (111/10W)
         Chicago, Illinois 60690-0755                By:      /s/ Thad D. Rasche
         Fax:  (312) 461-5225                        Title:   Vice President


Address:                                             FIRSTAR BANK, N.A.

         1350 Euclid Avenue, ML 4432
         Cleveland, Ohio 44115                       By:      /s/ John D. Barrett
         Fax:  (216) 623-9280                        Title:   Senior Vice President
</TABLE>


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                                    EXHIBIT E

                                COMPLIANCE REPORT

                                                               ___________, 19__


To:      National City Bank

Subject:          Amended and Restated Credit Agreement dated as of December 13,
                  1994, as amended, with the Banks that are parties thereto and
                  National City Bank as agent (the "Credit Agreement")

Greetings:

Pursuant to subsection 3A.01 of the subject Credit Agreement and in my capacity
as the chief financial officer of Brush Wellman Inc., I hereby certify that to
the best of my knowledge and belief

         (a) the financial statements of the Companies accompanying this letter
         are true and complete and fairly present in all Material respects their
         consolidated financial condition as of _____________________, _____
         (the "Closing Date") and the consolidated results of their operations
         for the fiscal period then ending,

         (b) no Default under the Credit Agreement exists *[except for those
         which, together with our intentions in respect thereof, are set forth
         in Exhibit One to this letter] and

         (c) as indicated by the calculations below, the Companies are *[not] in
         full compliance with subsections 3B.01 through 3B.04, both inclusive.

         [* - In (b) and (c), delete the bracketed language if inapplicable.]

3B.01 The actual amount of the Companies' Tangible Net Worth at the Closing Date
is equal to or is greater than the required amount.

                   $190,731,000
       plus        $__________ 40% of     $_________

annual earnings accumulated from December 31, 1997 to the end of the preceding
fiscal year (see Section 3B.01)

       sum         $__________      required amount
                   $__________      actual Tangible Net Worth

3B.02 The Funded Indebtedness of the Companies does not exceed an amount equal
to the Leverage Multiplier times the Companies' EBITDA for the four consecutive
fiscal quarters most recently ended -- the Leverage Multiplier being (i) from
April 1, 1999, to September 30, 1999,


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inclusive, 4.25, (ii) from October 1, 1999, to December 31, 1999, inclusive,
4.00, (iii) from January 1, 2000, to March 31, 2000, inclusive, 3.75, (iv) from
April 1, 2000, to June 30, 2000, inclusive, 3.50, (v) from July 1, 2000, to
December 31, 2000, inclusive, 3.25, and (vi) on and after January 1, 2001, 3.00.

                  $______________           Funded Indebtedness
divided by        $______________           EBITDA
                  $______________           EBIT
                  $______________           Depreciation
                  $______________           Amortization

quotient          _______________

3B.03  [Intentionally Omitted]

3B.04 The actual Interest Coverage Ratio is greater than the minimum factor
(5:00 to 1:00) required, the Interest Coverage being a factor equal to the
quotient of the sum of items (a), (b) and (c) below divided by item (b).

         (a) $__________  Net Income
plus     (b) $__________  interest expense (including any required
                               capitalized interest)
plus     (c) $__________  income taxes
sum      (d) $__________  total
quotient (e)  __________  Actual Interest Coverage--(d)/(b)

3B.05 The actual Funded Debt of the Companies is equal to or less than the
maximum factor permitted, namely, 0.5 through December 31, 2000, and 0.45 on and
after January 1, 2001-- the Funded Debt being a factor equal to the quotient of
Funded Indebtedness divided by Funded Indebtedness plus Tangible Net Worth.

                    $_________      Funded Indebtedness
         divided by $_________      Funded Indebtedness plus Tangible Net Worth
         quotient    _________      Actual Funded Indebtedness


                               BRUSH WELLMAN INC.



                                         By:______________________________
                                         Title: ____________________________


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