EXHIBIT 5.1


                                     February 24, 2005



Phibro Animal Health Corporation
65 Challenger Road
Ridgefield, New Jersey 07660


   Re: Phibro Animal Health Corporation Registration Statement on Form S-4
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Ladies and Gentlemen:

         We have acted as counsel to Phibro Animal Health Corporation, a New
York corporation (the "Company"), and the Designated Guarantors (as hereinafter
defined), in connection with the public offering of 127,491 units, consisting of
$103.207 million principal amount of new 13% Senior Secured Notes due 2007 (the
"New U.S. Notes") of the Company and $24.284 million principal amount of new 13%
Senior Secured Notes due 2007 (the "New Dutch Notes" and together with the New
U.S. Notes, the "New Notes") of Philipp Brothers Netherlands III B.V. (the
"Dutch Issuer"). The New U.S. Notes will be guaranteed, on a senior secured
basis pursuant to the guarantees (the "Domestic Guarantees" and, together with
the New Notes, the "New Domestic Securities") by Phibro-Tech, Inc., a Delaware
corporation, Prince Agriproducts, Inc., a Delaware corporation, Koffolk, Inc., a
Delaware corporation, C P Chemicals, Inc., a New Jersey corporation, Phibrochem,
Inc., a New Jersey corporation, Phibro Chemicals, Inc., a New York corporation,
Phibro Animal Health U.S., Inc., a Delaware corporation, Phibro Animal Health
Holdings, Inc., a Delaware corporation, and Western Magnesium Corp., a
California corporation (collectively, the "Domestic Guarantors"). We have also
acted as special New York counsel to the Dutch Issuer in connection with the New
Dutch Notes and to Phibro Animal Health SA ("Phibro Belgium") and the Company in
connection with their guarantees thereof. The New Domestic Securities, together
with the New Dutch Note and the guarantees thereof by the Company and Phibro
Belgium are referred to collectively as the "New Securities"). The seven
Domestic Guarantors that are incorporated under the laws of the States of New
York, Delaware or New Jersey are collectively referred to as the "Designated
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 13% Senior Secured Notes due 2007 of the Company and of the Dutch
Issuer (collectively, the "Old Securities") under an Indenture, dated as of
October 21, 2003 as supplemented as of December 21,

Phibro Animal Health Corporation
February 24, 2005
Page 2

2004 (the "Indenture"), by and among the Company, the Dutch Issuer, the Domestic
Guarantors and HSBC Bank USA, National Association, as trustee (the "Trustee"),
as contemplated by the Registration Rights Agreements dated October 21, 2003 and
December 21, 2004 (the "Registration Rights Agreement"), by and among the
Company, the Dutch Issuer, the Domestic Guarantors and Jefferies & Company, 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 the filing of the Registration
Statement (as hereinafter defined) and for no other purpose.

         In connection with this opinion, we have examined originals or copies,
certified or otherwise identified to our satisfaction, of (i) the Registration
Statement on Form S-4 (File No. 333-122063) as filed with the Securities and
Exchange Commission (the "Commission") on January 12, 2005 under the Act, and
Amendment No. 1 thereto as filed with the Commission on February 2, 2005 and
Post-Effective Amendment No. 1 thereto as filed with the Commission on February
24, 2005 (such Registration Statement, as so amended, being hereinafter referred
to as the "Registration Statement"); (ii) an executed copy of the Registration
Rights Agreement; (iii) an executed copy of the Indenture; (iv) the Certificate
of Incorporation of the Company, and the Certificate of Incorporation of each of
the Designated Guarantors, each as amended to date; (v) the By-Laws of the
Company, and the By-Laws of each of the Designated Guarantors, each as amended
to date; (vi) Certificates issued by the Secretary of State of the States of New
York, Delaware and New Jersey, certifying the existence of the Company and each
of the Designated Guarantors and its respective authority to transact business
in its state of incorporation; (vii) certain resolutions adopted by the Board of
Directors and shareholders of the Company, relating to the Exchange Offer, the
issuance the New Securities issued by it, the Indenture and related matters,
certified by the Secretary of the Company as true and complete; (viii) certain
resolutions adopted by the Board of Directors and shareholders of each of the
Designated Guarantors relating to, among other things, the issuance of the
Domestic Guarantees by the Designated Guarantors, certified by the Secretary of
each of the applicable Designated Guarantors as true and complete; (ix) the Form
T-1 of the Trustee filed as an exhibit to the Registration Statement; and (x)
the form of the New Notes (including the form of Domestic Guarantees). We have
also examined originals or copies, certified or otherwise identified to our
satisfaction, of such records of the Company and the Designated Guarantors and
such agreements, certificates of public officials, certificates of officers or
other representatives of the Company, the Designated Guarantors and others, and
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 (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,

Phibro Animal Health Corporation
February 24, 2005
Page 3

conformed or photostatic copies or by electronic means and the authenticity of
the originals of such latter documents; (ii) that all parties other than the
Company and the Designated Guarantors 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 by all requisite action, corporate
or other, by each part thereto (other than the Company and the Domestic
Guarantors), and have been duly authorized by all requisite action, corporate or
others, and 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 and shareholders of the Company and
the Designated Guarantors in connection with the Purchase Agreement dated
October 21, 2003 and December 21, 2004 between the Company, the Dutch Issuer and
Jefferies & Company, Inc. and the sale of the Old Securities have not been
rescinded and revoked, (v) the satisfaction of all the requirements with respect
to the execution, delivery and performance of the New Securities and other
documents securing any thereof by each party to each document (other than the
Company and the Designated Guarantors); and (vi) that each part to any of the
documents (other than the Company and the Designated Guarantors) has complied
with all laws, rules, orders and regulations applicable to it other than
Applicable Laws (defined below) and has taken or obtained all actions, consents,
approvals, authorizations, filings, exemptions, registrations, qualifications,
orders and notations necessary under all applicable laws, rules, regulations and
orders other than the Applicable Laws ("Foreign Laws") (without resort to
principles of estoppel, apparent authority, waiver or the like) to bind it under
the documents to which it is a party, including without limitation the issuance
and sale of the New Dutch Notes and the execution, delivery and performance of
each document to which it is a party and the consummation of the transactions
contemplated by the Registration Rights Agreement. We have also assumed (i) that
the execution, delivery and performance of the Guarantees and the Indenture by
each of the Guarantors incorporated under the laws of California will not
violate any provisions of the laws of such state, (ii) the validity, binding
effect and enforceability of the Indenture and the Guarantees of the Guarantors
incorporated under the laws of California under the laws of such state, and
(iii) that the laws of such jurisdictions would not affect any of the
conclusions stated herein. As to any fact material to the opinions expressed
herein which we have not independently established or verified, we have relied
upon statements and representations of officers and other representatives of the
Company, the Dutch Issuer, the guarantors of the New Notes and others. In
addition, we have assumed that there will be no changes in applicable law
between the date of this opinion and the date of issuance and delivery of the
New Securities.

         Members of our firm are admitted to the bar in the State of New York
(without regard to conflict of laws) 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, the laws of the State of New York and, to the extent
necessary to render this opinion, the Delaware corporate law and the New Jersey
corporate law. Such laws as to which we express an opinion are referred

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February 24, 2005
Page 4

to as "Applicable Laws." In this regard, we express no opinion as to the
legality, binding effect, validity, enforceability or interpretation of any
agreement or instrument or any provision thereof to the extent that such
purports to be or is in fact governed by the internal laws of any jurisdiction
or any law other than the federal laws of the United States of America and the
State of New York. We have assumed for purposes of this letter, that the
internal laws of the State of New York in each case without regard to conflict
of laws principles would apply to each of the documents and to each other
document relevant to our opinions, notwithstanding any choice of law provision
contained in, or law of any other jurisdiction applicable to, any of the
documents, or any such other document, or any issuer or guarantor, including the
State of New Jersey, the Netherlands, Belgium or the European Union. We express
no opinion as to any local laws or ordinances.

         In connection with our opinions with respect to any issuer or guarantor
organized under a Foreign Law or with respect to the validity, binding nature or
enforceability against any of them of any documents signed by any of them or to
which any of them is bound, no opinion is expressed that a remedy will be
available with respect to each covenant or agreement of such party or that any
such covenant or agreement will otherwise be given effect, or that any remedy
expressly provided for in any such document will be given effect as stated, and
we further assume that:

         (a) insofar as any obligation or right is to be performed in, or is
otherwise affected by the laws of, any jurisdiction other than the federal laws
of the United States and the laws of the State of New York, the performance of
any such obligation and the exercise of any such right would not be illegal or
ineffective under the laws of that jurisdiction;

         (b) any law, other than the federal laws of the United States and the
laws of the State of New York, which may apply to the formation, validity,
binding nature or enforceability of a contract or to any of the documents (or
the transactions contemplated thereby) would not be such as to affect any
opinion stated in this letter;

         (c) all of the conditions necessary under any of the Foreign Laws for
the formation, validity, binding nature and enforceability of a contract have
occurred, including its due authorization, execution and delivery and the
existence of adequate consideration;

         (d) the Units, to the extent of the obligations of the Dutch Issuer,
and the Dutch Notes, would be treated by all courts in the Netherlands as
constituting the legal, valid and binding obligations of the Dutch Issuer
enforceable against the Dutch Issuer in accordance with their respective terms,
and such documents are in proper form for their enforcement in such Dutch
courts.

Phibro Animal Health Corporation
February 24, 2005
Page 5

         (e) the Guarantee of Phibro Belgium would be treated by all courts in
Belgium as constituting the legal, valid and binding obligation of Phibro
Belgium enforceable against Phibro Belgium in accordance with its terms, and
such Guarantee is in proper form for its enforcement in such courts;

         (f) the choice of New York internal law (without regard to conflict of
laws principles) as the law governing the documents would be upheld as a valid
choice of law by the courts of the respective jurisdictions of organization of
the Dutch Issuer and Phibro Belgium, and applied by those courts in relation to
the documents as the governing law thereof; and

         (g) neither the execution, delivery or performance of any foreign
collateral documents, the issuance of Units by the Dutch Issuer or the Dutch
Notes or the consummation of any transactions contemplated therein or by the
Indenture conflicts with, violates, constitutes a breach of or a default (with
the passage of time or otherwise) under, requires the consent of any person
under, results in the imposition of a lien on any assets of any issuer or
guarantor (except for liens created pursuant to the collateral documents, also
as to which no opinion is expressed herein) or results in acceleration of
indebtedness under or pursuant to (i) any of the charter documents of the Dutch
Issuer or Phibro Belgium, (ii) any indenture, lease, note, contract or other
agreement or instrument which is binding on the Dutch Issuer or Phibro Belgium
or any of its properties (other than any thereof filed as an exhibit to the
Registration Statement), or (iii) any statute, law, rule or regulation of the
Netherlands, Belgium or European Union or any political subdivision thereof
binding on any issuer or guarantor or any of its properties, or any judgment,
order or decree of a Dutch, Belgium or European Union court or administrative or
regulatory body.

         Based upon and subject to the foregoing and the limitations,
assumptions, qualifications and exceptions set forth herein, we are of the
opinion that the New Securities have been duly authorized by the Company and the
Designated Guarantors, and 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, assuming the due authorization, execution and delivery of the
New Dutch Notes by the Dutch Issuer and of the guarantee thereof by Phibro
Belgium, the New Securities will constitute valid and binding obligations of the
Company and each of the Designated Guarantors, enforceable against the Company
and each of the Designated Guarantors in accordance with their respective terms.

         The opinion set forth above is qualified as follows:

Phibro Animal Health Corporation
February 24, 2005
Page 6

         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), 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 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, 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 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.


                                   Very truly yours,


                                   /s/ Golenbock Eiseman Assor Bell & Peskoe LLP
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