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                                                                   EXHIBIT (10t)

                                 AMENDMENT NO. 4
                                       TO
                               BRUSH WELLMAN INC.
                      SUPPLEMENTAL RETIREMENT BENEFIT PLAN
                         (December 1, 1992 Restatement)


         Brush Wellman Inc., an Ohio corporation, hereby adopts this Amendment
No. 4 to the Brush Wellman Inc. Supplemental Retirement Benefit Plan (December
1, 1992 Restatement) (the "Plan").

                                       I.

         Article VI of the Plan is amended by adding at the end thereof the
following:

         Section 6.7 -- 1999 Special Election

                  Notwithstanding any other provision of the Plan to the
         contrary, except Section 9.5 (as contemplated in this Section 6.7),
         each of David C. Deubner and John J. Pallam, may elect to forego all
         rights and benefits under the Plan with respect to his Supplemental
         Savings Plan Account in consideration of an award of "Options", as
         defined in the Brush Wellman Inc. Key Employee Share Option Plan (the
         "KESOP"), in accordance with the following and such rules and
         procedures as may be established by the Committee consistent with the
         following:

                  (i)      Such election may be made only by delivery during a
                           period occurring in 1998, which period shall begin
                           and shall end prior to the effective date of the
                           election, by the Participant to the Company of a
                           written election on a form prescribed therefor by the
                           Committee, which form shall be substantially in the
                           form of Exhibit II attached hereto and made a part
                           hereof;

                  (ii)     In the case of a Participant who makes the election
                           provided for under this Section 6.7, neither the
                           Participant, the Participant's Beneficiary, nor any
                           other person claiming through or under the
                           Participant shall thereafter have any rights under or
                           with respect to Article VI of the Plan and all
                           provisions of the Plan shall be construed,
                           interpreted, and applied accordingly;

                  (iii)    In the case of Participant who makes the election
                           provided for under this Section 6.7 and who would
                           have credits to his Supplemental Savings Plan Account
                           occur under Section 6.2 after


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                           the effective date of such election without regard to
                           this Section 6.7, such credits shall not occur but
                           such Participant's Excess Credited Compensation shall
                           be reduced without regard to the election under this
                           Section 6.7;

                  (iv)     The provisions of this Section 6.7 shall not result
                           in any right of a Participant to receive Excess
                           Credited Compensation that such Participant has
                           elected to reduce;

                  (v)      The terms and conditions of Options awarded under the
                           KESOP in respect of any election under this Section
                           6.7 shall be determined under the KESOP;

                  (vi)     Such election shall include a consent to Amendment
                           No. 4 to the Plan in accordance with Section 9.5 of
                           the Plan and a consent under the Trust Agreement for
                           Brush Wellman Inc. Supplemental Retirement Benefit
                           Plan dated January 8, 1993 (the "Trust Agreement"),
                           to Amendment No. 2 to the Trust Agreement, which
                           Amendment No. 2 to the Trust Agreement provides for
                           return to the Company of any assets of the
                           Participant's separate account(s) under the Trust
                           Agreement;

                  (vii)    Such election shall be irrevocable after delivery
                           thereof to the Company, and such election shall
                           (except as otherwise provided in clause (viii) below)
                           become effective upon delivery thereof to the
                           Company; and

                  (viii)   Notwithstanding the foregoing provisions of this
                           Section 6.7, if the employment with the Controlled
                           Group of any Participant described in this Section
                           6.7 shall terminate prior to the effective date of
                           his election made pursuant to this Section 6.7 the
                           provision of this Section 6.7 shall not apply with
                           respect to such Participant and any election of such
                           Participant made pursuant to this Section 6.7 shall
                           be void ab initio.

                                       II.

         The changes to the Plan made by Section I of this Amendment No. 4 shall
be effective beginning December 1, 1998.

         Executed at Cleveland, Ohio this _____ day of _______________, 1998.


                                             BRUSH WELLMAN INC.

                                             By:

                                             Title:____________________________