[Letterhead of Schmiedeskamp, Robertson, Neu & Mitchell]
                 
                              December 17, 1998



Philipp Brothers Chemicals, Inc.
One Parker Plaza
Fort Lee, NJ 07024

         Re:  Philipp Brothers Chemicals, Inc. Registration Statement 
              on Form S-4

Dear Sirs:

         We have acted as special counsel to The Prince Manufacturing Company,
an Illinois corporation (the "Subsidiary"), in connection with the public
offering of $100,000,000 aggregate principal amount of 9 7/8% Senior
Subordinated Notes due 2008 (the "New Notes") of Philipp Brothers Chemicals,
Inc., a New York corporation (the "Company"), which will be guaranteed, on a
senior subordinated basis pursuant to the guarantees (the "Guarantees" and,
together with the New Notes, the "New Securities") by the Subsidiary,
Phibro-Tech, Inc., a Delaware corporation, Prince Agri Products, Inc., a
Delaware corporation, MRT Management Corp., a Delaware corporation, Mineral
Resource Technologies, L.L.C., a limited liability company formed under the
laws of Delaware, Koffolk, Inc., a Delaware corporation, C.P. Chemicals, Inc.,
a New Jersey corporation, Phibrochem, Inc., a New Jersey corporation, the
Prince Manufacturing Company, a Pennsylvania corporation, Phibro Chemicals,
Inc., a New York corporation and Western Magnesium Corp., a California
corporation (collectively, the "Guarantors"). The New Securities are to be
issued pursuant to an exchange offer (the "Exchange Offer") in exchange for a
like principal amount of the issued and outstanding 9 7/8% Senior Subordinated
Notes due 2008 of the Company (the "Old Securities") under an Indenture dated
as of June 11, 1998 (the "Indenture"), by and among the Company, the
Guarantors and The Chase Manhattan Bank, as trustee (the "Trustee"), as
contemplated by the Registration Rights Agreement dated June 11, 1998 (the
"Registration Rights Agreement"), by and among the Company, the Guarantors and
Schroder & Co. Inc.

         This opinion is being furnished to you in accordance with the
requirements of Item 601(b)(5) of Regulation S-K under the Securities Act of
1933, as amended (the "Act").

         In connection with this opinion, we have examined originals or
copies, certified or otherwise identified to our satisfaction, of the
following documents:






Philipp Brothers Chemicals, Inc.
December 17, 1998
Page 2



         (i) The Registration Statement on Form S-4 (File No. 333-64641) as
filed by the Company with the Securities and Exchange Commission (the
"Commission") on September 29, 1998 and 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 (collectively, the "Registration Statement");

         (ii)  an executed copy of the Registration Rights Agreement;

         (iii) an executed copy of the Indenture;

         (iv)  the Articles of Incorporation of the Subsidiary certified as
true and correct by the Secretary of State of the State of Illinois on May 18,
1998;

         (v)   the Bylaws of the Subsidiary, certified as true and complete 
by an officer of the Subsidiary;

         (vi)  copies of resolutions of the Board of Directors of the
Subsidiary authorizing and approving, among other things, the execution and
delivery of the Indenture and the Guarantees, certified by the Secretary of
the Subsidiary as true and complete;

         (vii)  the Form T-1 of the Trustee filed as an exhibit to the
Registration Statement; and

         (viii) the form of the New Notes and the Guarantees.

         Items (i) - (viii) above are hereinafter referred to as the Examined
Documents. Capitalized words and phrases having a defined meaning in the
Examined Documents shall have the same meanings when used herein unless
otherwise defined.

         We have also examined originals or copies, certified or otherwise
identified to our satisfaction, of such other documents, certificates and
records as we have deemed necessary or appropriate as a basis for the opinions
set forth herein.

         In rendering these opinions we have assumed, with your permission and
without having made any independent investigation of the facts: (i) the
genuineness of all signatures, the legal capacity of all natural persons, the
authenticity of all Examined Documents submitted to us as originals, the
conformity to original documents of all Examined Documents submitted to us as
certified or photostatic copies and the authenticity of the originals of such
latter documents; (ii) that all parties other than the Subsidiary have the
power, corporate or otherwise, to enter into and perform all





Philipp Brothers Chemicals, Inc.
December 17, 1998
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obligations under all Examined Documents we have reviewed in connection with
these opinions; (iii) that all the Examined Documents have been duly
authorized, executed and delivered by, and each of them constitutes the
legally valid and binding obligation of, such other parties, as applicable,
enforceable against such other parties in accordance with their respective
terms; (iv) that the resolutions of the Board of Directors of the Subsidiary
in connection with the Purchase Agreement dated June 5, 1998 between the
Company and Schroder & Co. Inc. and the sale of the Old Securities have not
been rescinded and revoked; and (v) that all material factual matters,
including, without limitation, representations and warranties, contained in
the Examined Documents are true and correct as set forth therein.

         We note that the Indenture is by its terms governed by the laws of
the State of New York. We are not admitted to practice in the State of New
York, and accordingly express no opinion as to the laws of the State of New
York. We express no opinion as to the validity of such choice of law. Our
opinion should be understood to the effect to be given to such documents under
the internal laws of the State of Illinois, if a court were to apply such law
notwithstanding the parties' choice of other law.

         Members of our firm are admitted to the bar in the State of Illinois
and we express no opinion with regard to any matter which may be governed by
any law other than the federal law of the United States of America and the
laws of the State of Illinois.

         Based upon and subject to the limitations, assumptions,
qualifications and exceptions set forth herein, we are of the opinion that
when (i) the Registration Statement becomes effective under the Act and the
Indenture has been qualified under the Trust Indenture Act of 1939, as
amended, and (ii) the New Securities have been duly executed and authenticated
in accordance with the terms of the Indenture and have been delivered upon
consummation of the Exchange Offer against receipt of Old Securities
surrendered in exchange therefor in accordance with the terms of the Exchange
Offer, the Guarantee of the Subsidiary will constitute a valid and binding
obligation of the Subsidiary, enforceable against such Subsidiary in
accordance with its terms.

         The opinion set forth above is qualified further as follows:

         A. The validity and enforceability of obligations, and the
availability of rights and remedies, under the Indenture and under the
Guarantees are subject to and may be limited or affected by (i) bankruptcy,
insolvency, reorganization, moratorium or similar laws now or hereafter in
effect affecting creditors' rights generally (including, without limitation,
Section 548 of the United States Bankruptcy Code, state fraudulent transfer
laws and other similar laws relating to fraud on creditors ("Fraudulent
Conveyance Laws")), and (ii) general principles of equity 





Philipp Brothers Chemicals, Inc.
December 17, 1998
Page 4


regardless of whether the validity or enforceability of obligations or
availability of rights and remedies is considered in a proceeding in equity or
at law .

         B. The validity and enforceability of obligations, and the
availability of rights and remedies, under the Indenture and the Guarantees
may be further limited by other laws and judicial decisions with respect to or
affecting remedial or procedural provisions contained in such documents.
However, in our judgment and subject to the other qualifications set forth in
this letter, such other laws and judicial decisions do not render the
Indenture invalid as a whole or substantially interfere with realization of
the principal benefits intended to be provided thereby.

         C. The validity and enforceability of obligations, and the
availability of rights and remedies, under the Indenture, including the
Guarantees under the Indenture, may be further limited by other laws and
judicial decisions with respect to the enforceability of any waiver granted
under Section 6.04 of the Indenture.

         We hereby consent to the filing of this opinion with the Commission
as an exhibit to the Registration Statement. We also consent to the reference
to our firm under the caption "Legal Matters" in the Registration Statement.
In giving this consent, we do not thereby admit that we are included in the
category of persons whose consent is required under Section 7 of the Act or
the rules and regulations of the Commission. Best regards.

                                Yours truly,

                                Schmiedeskamp, Robertson, Neu & Mitchell


                                William M. McCleery, Jr.