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                                                                   Exhibit 4.1.1


            FIRST SUPPLEMENTAL INDENTURE ("First Supplemental Indenture"), dated
as of January 15, 1999, among Philipp Brothers Chemicals, Inc., a New York
corporation (the "Company"), each of the Guarantors named herein, as guarantors,
and The Chase Manhattan Bank, as Trustee (the "Trustee").

            WHEREAS, the Company, the Guarantors and the Trustee have heretofore
executed and delivered to the Trustee an Indenture dated as of June 11, 1998
(the "Original Indenture"), providing for the issuance of the Initial Notes and
the Exchange Notes;

            WHEREAS, pursuant to the Registration Rights Agreement, the Company
filed a Registration Statement on Form S-4 (File No. 333-64641) with the
Securities and Exchange Commission (the "Commission") on September 29, 1998
under the Securities Act of 1933, as amended (the "Act"), as amended by
Amendment No. 1 thereto as filed with the Commission on November 23, 1998,
Amendment No. 2 thereto as filed with the Commission on December 14, 1998, and
Amendment No. 3 thereto filed with the Commission on December 17, 1998 (such
Registration Statement, as so amended, being hereinafter referred to as the
"Registration Statement"), in connection with the Company's offer to exchange
(the "Exchange Offer") the aggregate principal amount of the unregistered
Initial Notes for a like principal amount of Exchange Notes, as registered under
the Act pursuant to the Registration Statement;

            WHEREAS, the Registration Statement was declared effective by the
Commission on December 17, 1999 and, pursuant to the Registration Rights
Agreement, the Exchange Offer was consummated on January 15, 1999;

            WHEREAS, Section 9.01 of the Original Indenture provides that the
Company and the Trustee may execute this First Supplemental Indenture without
notice to or the consent of any Holder to provide for issuance of the Exchange
Notes;

            WHEREAS, the execution and delivery of this First Supplemental
Indenture and the Exchange Notes and Guaranties substantially in the form of
Exhibits B and F to the Indenture, respectively, have been authorized by
resolution of the respective Boards of Directors and shareholders of the Company
and the Guarantors;

            WHEREAS, the Company and the Guarantors authorize the Trustee to
cancel the Initial Notes and related Guarantees and to authenticate the Exchange
Notes and related Guarantees in replacement therefor;


            WHEREAS, all conditions and requirements necessary to make this
First Supplemental Indenture and the Exchange Notes the valid obligations of the
Company, and to make this First Supplemental Indenture and the Guarantees
relating to the Exchange Notes a valid and binding agreement of each of the
Guarantors, have been performed and fulfilled by the applicable parties hereto
and the execution and delivery hereof and thereof have been in all


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respects duly authorized by the applicable parties hereto.

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

                                 ARTICLE ONE

                                EXCHANGE OFFER

            SECTION 1.01. Exchange of Initial Notes for Exchange Notes.

            Promptly following the execution and delivery of this First
Supplemental Indenture, the Trustee shall, upon the written order of the Company
in the form of an Officers' Certificate of the Company, authenticate and deliver
Exchange Notes substantially in the form of Exhibit B to the Indenture in
replacement of Initial Notes whose Holders have accepted the Exchange Offer and
exchanged their Notes in accordance therewith, and upon delivery of certificates
representing the Initial Notes to the Trustee for cancellation, the Trustee
shall cancel such Initial Notes.

                                   ARTICLE TWO

                                  MISCELLANEOUS

            SECTION 2.01. Execution of Supplemental Indenture; Modification of
Original Indenture.

            This First Supplemental Indenture is executed and shall be construed
as an indenture supplemental to the Original Indenture and, as provided in the
Original Indenture, this First Supplemental Indenture forms a part thereof.

            Except as otherwise expressly provided for in this First
Supplemental Indenture, all of the terms and conditions of the Original
Indenture are hereby ratified and shall remain unchanged and continue in full
force and effect.

            SECTION 2.02. Concerning the Trustee.

            The recitals contained herein, shall be taken as the statements of
the Company and the Guarantors and the Trustee assumes no responsibility for the
correctness of same. The Trustee makes no representations as to the validity or
sufficiency of this First Supplemental Indenture or of the Notes.


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            SECTION 2.03. Counterparts.

            This First Supplemental Indenture may be executed in any number of
counterparts, each of which when so executed shall be deemed to be an original,
but all of such counterparts shall together constitute but one and the same
instrument.

            SECTION 3.03. Governing Law.

            This First Supplemental Indenture shall be governed by and
construed in accordance with the laws of the State of New York.


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                               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.

                                    PHILIPP BROTHERS CHEMICALS, INC.


                                    By:   /s/ Jack C. Bendheim
                                          ----------------------
                                          Name:  J. C. Bendheim
                                          Title:   President

                                    CP CHEMICALS, INC., as Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    PHIBRO-TECH, INC., as Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    MRT MANAGEMENT CORP., as Guarantor


                                    By:   /s/ Nathan Bistricer
                                          ---------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President


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                                    MINERAL RESOURCE TECHNOLOGIES,
                                    L.L.C., as Guarantor

                                    By: MRT Management Corp.,
                                    Managing Member

                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    PRINCE AGRIPRODUCTS, INC., as
                                    Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    PHIBROCHEM, INC., as Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    PHIBROCHEMICALS, INC., as Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President



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                                    WESTERN MAGNESIUM CORP., as
                                    Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    THE PRINCE MANUFACTURING COMPANY,
                                    as Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    THE PRINCE MANUFACTURING COMPANY,
                                    as Guarantor


                                    By:   /s/ Nathan Bistricer
                                          -----------------------
                                          Name:  Nathan Bistricer
                                          Title: Vice President

                                    THE CHASE MANHATTAN BANK, as Trustee


                                    By:   /s/ Sheik Witlshire
                                          ----------------------
                                          Name:  Sheik Wiltshire
                                          Title: Second Vice President


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