[Letterhead of Blanc Williams Johnston & Kronstadt]

                               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 Western Magnesium Corp., a
California corporation (the "Subsidiary"), in connection with the public
offering of $100,000,000 aggregate principal amount of 97/8% 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 Agriproducts, 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
Price Manufacturing Company, an Illinois corporation, The Prince Manufacturing
Company, a Pennsylvania corporation and Phibro Chemicals, Inc., a New York
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 97/8% 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, Amendment No. 1 thereto as filed with the
Commission on November 23, 1998, and Amendment No. 2 thereto as filed with the
Commission on December 17, 1998 and (as amended, 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 California on
December 2, 1998;

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

          (vi) Certificate dated December 2, 1998 issued by the Secretary of 
State of the State of California certifying the existence of the Subsidiary and
its respective authority to transact business in corporate form in the State of
California;

          (vii) copies of resolutions of the Board of Directors of the 
Subsidiary authorizing and approving, among other things, the issuance of the
New Securities and the Exchange Offer, certified by the Secretary of Subsidiary
as true and complete;

         (viii) the Form T-1 of the Trustee filed as an exhibit to the 
Registration Statement; and (ix) the form of the New Notes and the Guarantees.

         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 documents submitted to us as originals, the conformity to
original documents of all 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 obligations under all
documents we have examined in connection with these opinions (the "Examined
Documents"); (iii) that all the Examined Documents have been duly authorized,
executed and delivered by, and each of them constitutes the legally valid and

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Philipp Brothers Chemicals, Inc.
December 17, 1998
Page 3


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 such State. 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 California 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
California 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 California.

         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 the Subsidiary in accordance
with its terms.

         The opinion set forth above is qualified as follows:

         A. The validity and enforceability of obligations, and the 
availability of rights and remedies, under the Indenture, including the
Guarantees under the Indenture, 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, regardless of whether
such validity or enforceability of obligations or availability of rights and
remedies is considered in a 

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


proceeding in equity or at law.

         B. The validity and enforceability of obligations, and the 
availability of rights and remedies, under the Indenture and under 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, but 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 availability 
of rights and remedies, under the Indenture and the Guarantees, 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.

                                           Very truly yours,



                                           Blanc Williams Johnston & Kronstadt


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