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EXHIBIT 4.3


       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, and
            KAISER TEXAS MICROMILL HOLDINGS, LLC, as
                     Subsidiary Guarantors
                                
                              and
                                
        STATE STREET BANK AND TRUST COMPANY, as Trustee

                                
                 SECOND SUPPLEMENTAL INDENTURE
                                
                  Dated as of February 1, 1996
                                
                               to
                                
INDENTURE

Dated As of February 1, 1993

                                       

12 % Senior Subordinated Notes due 2003

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         SECOND SUPPLEMENTAL INDENTURE, dated as of February 1,
1996, between 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"),and KAISER TEXAS
MICROMILL HOLDINGS, LLC, a Texas limited liability company
("Texas Holdings"),as Subsidiary Guarantors, and State Street
Bank and Trust Company (as successor to The First National Bank
of Boston), a Massachusetts trust company, as Trustee (the
"Trustee").

         WHEREAS, the Company, KAAC, AJI, KJC and The First
National Bank of Boston executed an Indenture, dated as of
February 1, 1993 (the "Original Indenture"), in respect of
$400,000,000 aggregate principal amount of the Company's 12 %
Senior Subordinated Notes due 2003 (the "Securities"), and the
Original Indenture was amended by a First Supplemental Indenture,
dated as of May 1, 1993 (the Original Indenture, as amended by
such First Supplemental Indenture being hereinafter referred to
as the "Indenture"), executed by the Company, KACC, AJI, KJC and
Kaiser Finance;

         WHEREAS, State Street Bank and Trust Company is the
successor to The First National Bank of Boston, as Trustee under
the Indenture;

         WHEREAS, Section 5.12 of the Indenture requires, under
circumstances specified in Section 5.12, 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 Second 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 and the Trustee
hereby amend the Indenture and agree that each of KMH, KSM, Texas
Sierra and Texas Holdings 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
each of KMH, KSM, Texas Sierra and Texas Holdings.


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                            ARTICLE II

                     MISCELLANEOUS PROVISIONS

         Section 2.1.  Terms Defined.  For all purposes of this
Second Supplemental Indenture, except as otherwise defined or
unless the context otherwise requires, terms used in capitalized
form in this Second 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 Second 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 and Texas Holdings in this Second Supplemental Indenture
and the Securities shall bind its successors and assigns.

         Section 2.5.  Multiple Counterparts.  This Second
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
Second Supplemental Indenture shall become effective immediately
upon its execution and delivery by the Trustee in accordance with
the provisions of Article Eleven of the Indenture. 

         Section 2.7.  Trustee Disclaimer.  The Trustee accepts
the amendment of the Indenture effected by this Second
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 and Texas Holdings, or for or with respect
to (i) the validity, efficacy or sufficiency of this Second
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 and Texas Holdings 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 and Texas
Holdings 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.



             [Remainder of Page Intentionally Blank]


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<PAGE>
                                
                            SIGNATURES

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

                             KAISER ALUMINUM & CHEMICAL
                             CORPORATION, as Issuer


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and
                                       Chief Financial Officer

Dated:  February 1, 1996


Attest:  By: ________________________
         Name:  Byron L. Wade
         Title:    Secretary

                             KAISER ALUMINA AUSTRALIA
                               CORPORATION, as a Subsidiary
                               Guarantor


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and
                                       Chief Financial Officer

Dated: February 1, 1996


Attest: By: _________________________
         Name:  Byron L. Wade
         Title:    Secretary

                             ALPART JAMAICA INC.,
                             as a Subsidiary Guarantor


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and
                                       Chief Financial Officer

Dated: February 1, 1996


Attest: By: ___________________________
         Name:  Byron L. Wade
         Title:    Secretary

                              -3-


<PAGE>
                                
                             KAISER JAMAICA CORPORATION,
                             as a Subsidiary Guarantor


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and
                                       Chief Financial Officer

Dated: February 1, 1996


Attest: By: ___________________________
         Name:  Byron L. Wade
         Title:    Secretary

                             KAISER FINANCE CORPORATION,
                             as a Subsidiary Guarantor


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and
                                       Chief Financial Officer

Dated: February 1, 1996


Attest: By: ___________________________
         Name:  Byron L. Wade
         Title:    Secretary

                             KAISER MICROMILL HOLDINGS, LLC,
                             as a Subsidiary Guarantor


                             By:_____________________________
                                  Name:  John T. La Duc
                                  Title:    Manager

Dated: February 1, 1996


Attest: By: ___________________________
         Name:  Anthony R. Pierno
         Title:    Manager







                              -4-


<PAGE>
                                
                             KAISER SIERRA MICROMILLS, LLC,
                             as a Subsidiary Guarantor


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and
                                       Chief Financial Officer

Dated: February 1, 1996


Attest: By: ___________________________
         Name:  Byron L. Wade
         Title:    Secretary

                             KAISER TEXAS SIERRA MICROMILLS,
                             LLC,
                             as a Subsidiary Guarantor


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and

                                       Chief Financial Officer

Dated: February 1, 1996


Attest: By: ___________________________
         Name:  Byron L. Wade
         Title:    Secretary

                             KAISER TEXAS MICROMILL HOLDINGS,
                             LLC,
                             as a Subsidiary Guarantor


                             By:______________________________
                                  Name:  John T. La Duc
                                  Title:   Vice President and
                                       Chief Financial Officer

Dated: February 1, 1996


Attest: By: ___________________________
         Name:  Byron L. Wade
         Title:    Secretary






                              -5-


<PAGE>
                                
                             STATE STREET BANK AND TRUST
                                 COMPANY, as Trustee


                             By:_____________________________
                                 Name:
                                 Title:

Dated: February 1, 1996


Attest: By: ___________________________
         Name:
         Title:









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