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        KAISER ALUMINUM & CHEMICAL CORPORATION, as Issuer,
                                 
              KAISER ALUMINA AUSTRALIA CORPORATION,
                       ALPART JAMAICA INC.,
                   KAISER JAMAICA CORPORATION,
                   KAISER FINANCE CORPORATION,
                 KAISER MICROMILL HOLDINGS, LLC,
                  KAISER SIERRA MICROMILLS, LLC,
               KAISER TEXAS SIERRA MICROMILLS, LLC,
            KAISER TEXAS MICROMILL HOLDINGS, LLC, and
                 KAISER BELLWOOD CORPORATION, as
                      Subsidiary Guarantors

                               and

           FIRST TRUST NATIONAL ASSOCIATION, as Trustee
                                 
                                 
                   FIRST SUPPLEMENTAL INDENTURE

                    Dated as of July 15, 1997

                                to

                            INDENTURE

                   Dated As of October 23, 1996
                                 
                                 
                                 
              10-7/8% Series B Senior Notes due 2006


---------------------------------------------------------------

          FIRST SUPPLEMENTAL INDENTURE, dated as of July 15,
1997, among KAISER ALUMINUM & CHEMICAL CORPORATION, a Delaware
corporation (the "Company"), as Issuer, KAISER ALUMINA AUSTRALIA
CORPORATION, a Delaware corporation ("KAAC"), ALPART JAMAICA
INC., a Delaware corporation ("AJI"), KAISER JAMAICA CORPORATION,
a Delaware corporation ("KJC"), KAISER FINANCE CORPORATION, a
Delaware corporation ("Kaiser Finance"), KAISER MICROMILL
HOLDINGS, LLC, a Delaware limited liability company ("KMH"),
KAISER SIERRA MICROMILLS, LLC, a Delaware limited liability
company ("KSM"), KAISER TEXAS SIERRA MICROMILLS, LLC, a Texas
limited liability company ("Texas Sierra"), KAISER TEXAS
MICROMILL HOLDINGS, LLC, a Texas limited liability company
("Texas Holdings"), and KAISER BELLWOOD CORPORATION, a Delaware
corporation ("Kaiser Bellwood"), as Subsidiary Guarantors, and
First Trust National Association, a national banking association,
as Trustee (the "Trustee").

          WHEREAS, the Company, KAAC, AJI, KJC, Kaiser Finance,
KMH, KSM, Texas Sierra, Texas Holdings, and the Trustee executed
an Indenture, dated as of October 23, 1996 (the "Indenture"), in
respect of $175,000,000 aggregate principal amount of the
Company's 10-7/8% Series B Senior Notes due 2006 (the
"Securities"); and

          WHEREAS, Section 4.12 of the Indenture requires, under
circumstances specified in Section 4.12, that the Company shall
cause certain Subsidiaries of the Company to execute and deliver
to the Trustee a supplemental indenture in form and substance
satisfactory to the Trustee pursuant to which such Subsidiaries
of the Company shall be named as additional Subsidiary
Guarantors; and

          WHEREAS, all conditions and requirements necessary to
make this First Supplemental Indenture a valid, binding and legal
instrument in accordance with its terms have been performed and
fulfilled and the execution and delivery hereof have been in all
respects duly authorized;

          NOW, THEREFORE, in consideration of the above premises,
each party agrees, for the benefit of the other and for the equal
and ratable benefit of the Holders of the Securities, as follows:

                            ARTICLE I
                                 
                            AMENDMENTS
                                 
          Section 1.  The Company, KAAC, AJI, KJC, Kaiser
Finance, KMH, KSM, Texas Sierra, Texas Holdings, Kaiser Bellwood,
and the Trustee hereby amend the Indenture and agree that Kaiser
Bellwood shall be a Subsidiary Guarantor for all purposes under
the Indenture and the term "Subsidiary Guarantor" shall for all
purposes under the Indenture specifically include Kaiser
Bellwood.



                           ARTICLE II

                     MISCELLANEOUS PROVISIONS

          Section 2.1.  Terms Defined.  For all purposes of this
First Supplemental Indenture, except as otherwise defined or
unless the context otherwise requires, terms used in capitalized
form in this First Supplemental Indenture and defined in the
Indenture have the meanings specified in the Indenture.

          Section 2.2.  Indenture.  Except as amended hereby, the
Indenture and the Securities are in all respects ratified and
confirmed and all their terms shall remain in full force and
effect.

          Section 2.3.  Governing Law.  This First Supplemental
Indenture shall be deemed to be a contract made under the laws of
the State of New York, and for all purposes shall be governed by
and construed in accordance with the laws of said state without
regard to the principles of the conflict of laws provisions
thereof.

          Section 2.4.  Successors and Assigns.  All agreements
of the Company, KAAC, AJI, KJC, Kaiser Finance, KMH, KSM, Texas
Sierra, Texas Holdings, and Kaiser Bellwood in this First
Supplemental Indenture and the Securities shall bind its
successors and assigns.

          Section 2.5.  Multiple Counterparts.  This First
Supplemental Indenture may be executed in any number of
counterparts, each of which shall be an original; but such
counterparts shall together constitute but one and the same
instrument.

          Section 2.6.  Effectiveness.  The provisions of this
First Supplemental Indenture shall become effective immediately
upon its execution and delivery by the Trustee in accordance with
the provisions of Article Ten of the Indenture.

          Section 2.7.  Trustee Disclaimer.  The Trustee accepts
the amendment of the Indenture effected by this First
Supplemental Indenture and agrees to execute the trust created by
the Indenture as hereby amended, but only upon the terms and
conditions set forth in the Indenture, including the terms and
provisions defining and limiting the liabilities and
responsibilities of the Trustee, which terms and provisions shall
in like manner define and limit its liabilities and
responsibilities in the performance of the trust created by the
Indenture as hereby amended, and, without limiting the generality
of the foregoing, the Trustee shall not be responsible in any
manner whatsoever for or with respect to any of the recitals or
statements contained herein, all of which recitals or statements
are made solely by the Company, KAAC, AJI, KJC, Kaiser Finance,
KMH, KSM, Texas Sierra, Texas Holdings, and Kaiser Bellwood, or
for or with respect to (i) the validity, efficacy or sufficiency
of this First Supplemental Indenture or any of the terms or
provisions hereof, (ii) the proper authorization hereof by the
Company, KAAC, AJI, KJC, Kaiser Finance, KMH, KSM, Texas Sierra,
Texas Holdings, and Kaiser Bellwood by corporate action or
limited liability company action or otherwise, (iii) the due
execution hereof by the Company, KAAC, AJI, KJC, Kaiser Finance,
KMH, KSM, Texas Sierra, Texas Holdings, and Kaiser Bellwood, or
(iv) the consequences (direct or indirect and whether deliberate
or inadvertent) of any amendment herein provided for, and the
Trustee makes no representation with respect to any such matters.


                            SIGNATURES
                                 
          IN WITNESS WHEREOF, the parties hereto have caused this
First Supplemental Indenture to be duly executed, all as of the
date first written above.


KAISER ALUMINUM & CHEMICAL
CORPORATION, as Issuer


By:   /s/ Karen A. Twitchell
   ------------------------
Name:   Karen A. Twitchell
Title:  Treasurer


Dated: July 15, 1997


Attest:  By:/s/ John Wm. Niemand II
            ------------------
Name:  John Wm. Niemand II
Title: Secretary

KAISER ALUMINA AUSTRALIA
CORPORATION, as a Subsidiary
Guarantor


By: /s/ Karen A. Twitchell
   -----------------------
Name:     Karen A. Twitchell
Title:     Treasurer


Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary


ALPART JAMAICA INC.,
as a Subsidiary Guarantor


By:/s/ Karen A. Twitchell
   ------------------------
Name:     Karen A. Twitchell
Title:     Treasurer


Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:      John Wm. Niemand II
Title:      Secretary


KAISER JAMAICA CORPORATION,
as a Subsidiary Guarantor


By:/s/Karen A. Twitchell   
     -----------------------
Name:  Karen A. Twitchell
Title: Treasurer


Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary

KAISER FINANCE CORPORATION,
as a Subsidiary Guarantor


By:/s/Karen A. Twitchell
   -------------------------
Name:     Karen A. Twitchell
Title:     Treasurer


Dated: July 15, 1997


Attest:  By:/s/ John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary


KAISER MICROMILL HOLDINGS,
LLC,
as a Subsidiary Guarantor


By:/s/Karen A. Twitchell
   ------------------------
Name:     Karen A. Twitchell
Title:     Treasurer

Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary


KAISER SIERRA MICROMILLS, LLC,
as a Subsidiary Guarantor


By:/s/Karen A. Twitchell
   -------------------------
Name:     Karen A. Twitchell
Title:     Treasurer

Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary


KAISER TEXAS SIERRA
MICROMILLS, LLC, as a
Subsidiary Guarantor


By:/s/Karen A. Twitchell
   --------------------------
Name:     Karen A. Twitchell
Title:     Treasurer


Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary


KAISER TEXAS MICROMILL
HOLDINGS, LLC, as a Subsidiary
Guarantor


By:/s/Karen A. Twitchell
   -------------------------
Name:     Karen A. Twitchell
Title:     Treasurer


Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary

KAISER BELLWOOD CORPORATION,
as a Subsidiary Guarantor


By:/s/ Karen A. Twitchell
   -------------------------
Name:     Karen A. Twitchell
Title:     Treasurer


Dated: July 15, 1997


Attest:  By:/s/John Wm. Niemand II
            ------------------
Name:     John Wm. Niemand II
Title:     Secretary








FIRST TRUST NATIONAL
ASSOCIATION, as Trustee


By:/s/Kathe Barrett
   ------------------------
     Name:Kathe Barrett
     Title: Trust Officer

Dated: July 15, 1997


Attest:  By:/s/Richard H. Prokosch
            ------------------
          Name: Richard H. Prokosch
          Title: Assistant
                 Secretrary