Exhibit 4.2.3
                            SECOND SUPPLEMENTAL INDENTURE
          THIS SECOND SUPPLEMENTAL INDENTURE, dated as of January 13, 1999 (this
"Second Supplemental Indenture"), to the Indenture (as defined below), among The
Doe Run Resources Corporation, a New York corporation (the "Company"), the
Guarantors (as defined in the Indenture), the Subsidiary of the Company listed
on Schedule A annexed hereto (the "Additional Guarantor") and State Street Bank
and Trust Company, as Trustee (the "Trustee").
          WHEREAS, the Company has issued its 111/4% Senior Secured Notes due
2005 (the "Securities") in the aggregate principal amount of $50,000,000 under
and pursuant to the Indenture, dated as of September 1, 1998 (the "Indenture"),
among the Company, the Guarantors named therein and the Trustee; and 
          WHEREAS, the Additional Guarantor has become a Restricted Subsidiary
and pursuant to Section 4.20 of the Indenture is entering into this Second
Supplemental Indenture to thereby become a Guarantor as provided in Article
Thirteen of the Indenture; and 
          WHEREAS, pursuant to Section 9.01(4) of the Indenture, the Company,
the Guarantors, the Additional Guarantor and the Trustee may enter into this
Second Supplemental Indenture without the consent of any Holder; and
          WHEREAS, all consents and notices required to be obtained and given as
conditions to the execution of this Second Supplemental Indenture pursuant to
the Indenture and all other documents relating to the Securities have been
obtained and given;
          NOW, THEREFORE, for and in consideration of the premises and the
mutual covenants and agreements hereinafter set forth, the parties hereto agree
as follows:
                                     ARTICLE I
                             AUTHORIZATION; DEFINITIONS
                                          
          Section 1.01.  SECOND SUPPLEMENTAL INDENTURE.  This Second
Supplemental Indenture is supplemental to, and is entered into, in accordance
with Section 9.01 of the Indenture, and except as modified, amended and
supplemented by this Second Supplemental Indenture, the provisions of the
Indenture are in all respects ratified and confirmed and shall remain in full
force and effect.
          Section 1.02.  DEFINITIONS.  Unless the context shall otherwise
require, all terms which are defined in Section 1.01 of the Indenture shall have
the same meanings, respectively, in this Second Supplemental Indenture as such
terms are given in said Section 1.01 of the Indenture.
                                     ARTICLE II
                                ADDITIONAL GUARANTOR
          Section 2.01.  ADDITIONAL GUARANTOR.  Pursuant to Section 13.01 of the
Indenture, the Additional Guarantor hereby expressly assumes the obligations of,
and otherwise agrees to perform all of the duties of, a Guarantor under the
Indenture, subject to the terms and conditions thereof, as of the date set forth
opposite the name of such Additional Guarantor on Schedule A hereto.
                                    ARTICLE III
                                   MISCELLANEOUS
                                          
          Section 3.01.  EFFECTIVE DATE.  This Second Supplemental Indenture
shall become effective upon execution and delivery hereof.
          Section 3.02.  COUNTERPARTS.  This Second Supplemental Indenture may
be executed in several counterparts, each of which shall be an original and all
of which shall constitute but one and the same instrument.
          Section 3.03.  ACCEPTANCE.  The Trustee accepts the Indenture, as
supplemented by this Second Supplemental Indenture, and agrees to perform the
same upon the terms and conditions set forth therein as so supplemented.  The
Trustee shall not be responsible in any manner whatsoever for or in respect of
the validity or sufficiency of this Second Supplemental Indenture or the due
execution by the Company, the Guarantors or the Additional Guarantor, or for or
in respect of the recitals contained herein, all of which are made solely by the
Company.
          Section 3.04.  SUCCESSORS AND ASSIGNS.  All covenants and agreements
in this Second Supplemental Indenture, by the Company, the Guarantors, the
Additional Guarantor or the Trustee shall bind its respective successors and
assigns, whether so expressed or not.  
          Section 3.05.  SEVERABILITY.  In case any provision in this Second
Supplemental Indenture shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby.
          Section 3.06.  GOVERNING LAW.  This Second Supplemental Indenture
shall be governed by and construed in accordance with the laws of the State of
New York, as applied to contracts made and performed within the State of New
York, without regard to principles of conflict of laws.  Each of the parties
hereto agrees to submit to the jurisdiction of the courts of the State of New
York in any action or proceeding arising out of or relating to this Second
Supplemental Indenture.
          Section 3.07.  INCORPORATION INTO INDENTURE.  All provisions of this
Second Supplemental Indenture shall be deemed to be incorporated in, and made
part of, the Indenture, and the Indenture, as amended and supplemented by this
Second Supplemental Indenture, shall be read, taken and construed as one and the
same instrument.   
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IN WITNESS WHEREOF, the parties have caused this Second Supplemental Indenture
to be duly executed as of the date first above written.
                                        THE DOE RUN RESOURCES CORPORATION
                                        By:  /s/ ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             Vice President and Chief Financial
                                             Officer
                                        FABRICATED PRODUCTS, INC.
                                        By:  /s/ ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             Vice President, Chief Financial
                                             Officer and Treasurer
                                        DOE RUN CAYMAN LTD.
                                        By:  /s/ ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             Vice President
                                        DOE RUN MINING S.R.L.
                                        By:  /s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
                                             General Manager
                                        DOE RUN PERU S.R.L.
                                        By:  /s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
                                             General Manager
                                        DOE RUN AIR S.A.C.
                                        By:  /s/ ▇▇▇▇▇ ▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇ ▇▇▇▇▇
                                             Finance Manager
                                        DOE RUN DEVELOPMENT S.A.C.
                                        By:  /s/ ▇▇▇▇▇▇ ▇▇▇▇ ▇▇▇▇▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇ ▇▇▇▇ ▇▇▇▇▇▇▇▇▇▇
                                             General Manager
                                          3
                                        EMPRESA MINERA COBRIZA S.A.
                                        By:  /s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
                                             General Manager
                                        DR LAND HOLDINGS, LLC
                                        By:  /s/ ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                             Vice President
                                        STATE STREET BANK AND TRUST COMPANY
                                        By:  /s/ ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇
                                             -----------------------------------
                                             ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇
                                             Vice President
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                                                                      SCHEDULE A
                                 ADDITIONAL GUARANTOR
NAME                                                                  DATE
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DR Land Holdings, LLC, a Delaware limited liability company . . January 13, 1999
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