<PAGE>   1
                                                                     EXHIBIT 4.1

                                                            SHARES
                                                            CUSIP 482730 10 8
                                                            SEE REVERSE FOR
                                                            CERTAIN DEFINITIONS

                                     K-TRON

                              K-TRON INTERNATIONAL

             INCORPORATED UNDER THE LAWS OF THE STATE OF NEW JERSEY

                                  COMMON STOCK

This Certifies that
is the owner of

FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK, PAR VALUE OF $.01 PER
SHARE,

                                       OF

                           K-TRON INTERNATIONAL, INC.

(hereinafter called the "Corporation"), transferable on the books of the
Corporation by the holder thereof, in person or by duly authorized attorney,
upon surrender of this certificate properly endorsed. This certificate is not
valid unless countersigned by the Transfer Agent and registered by the
Registrar.

         WITNESS the facsimile seal of the Corporation and the facsimile
signatures of its duly authorized officers.

DATED

                                            Countersigned and Registered:
                                            AMERICAN STOCK TRANSFER &
                                            TRUST COMPANY
                                                  (New York, New York)
                                                  Transfer Agent and Registrar
                                                  Authorized Signature

Mary E. Vaccara    Secretary      Edward B. Cloues, II   Chairman of the Board
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                           K-TRON INTERNATIONAL, INC.

                  THE CORPORATION WILL FURNISH TO ANY SHAREHOLDER WITHOUT CHARGE
         UPON REQUEST TO THE SECRETARY OF THE CORPORATION A FULL STATEMENT OF
         (1) THE DESIGNATIONS, RELATIVE RIGHTS, PREFERENCES AND LIMITATIONS OF
         THE SHARES OF PREFERRED STOCK AND COMMON STOCK OF THE CORPORATION SO
         FAR AS THE SAME HAVE BEEN DETERMINED AND (2) THE AUTHORITY OF THE BOARD
         OF DIRECTORS TO DIVIDE THE SHARES INTO CLASSES OR SERIES AND CHANGE THE
         RELATIVE RIGHTS, PREFERENCES, AND LIMITATIONS OF ANY CLASS OR SERIES.

         This certificate also evidences a beneficial interest in and entitles
the holder to certain Rights as set forth in the Rights Agreement between K-Tron
International, Inc. (the "Company") and First Interstate Bank of Arizona, N.A.
(the "Rights Agent") dated as of October 3, 1991 (the "Rights Agreement"), and
as the same may be amended from time to time, the terms of which are hereby
incorporated herein by reference and a copy of which is on file at the principal
offices of the Company. Under certain circumstances, as set forth in the Rights
Agreement, such Rights will be evidenced by separate certificates and beneficial
interests therein will no longer be evidenced by this certificate. The Company
will mail to the holder of this certificate a copy of the Rights Agreement, as
in effect on the date of mailing, without charge promptly after receipt of a
written request therefor. Under certain circumstances set forth in the Rights
Agreement, Rights issued to, or held by, any Person who is, was or becomes an
Acquiring Person or any Affiliate or Associate thereof (as such terms are
defined in the Rights Agreement), whether currently held by or on behalf of such
Person or by any subsequent holder, may become null and void.

         The following abbreviations, when used in the inscription on the face
of this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

TEN COM  --  as tenants in common            
                                                                
TEN ENT  --  as tenants by the entireties                       
JT TEN   --  as joint tenants with right of survivorship        
             and not as tenants in common                       

UNIF GIFT MIN ACT--.............Custodian.................
                      (Cust)                  (Minor)             
                   under Uniform Gifts to Minors    
                   Act....................................     
                                   (State)                 
     Additional abbreviations may also be used though not in the above list

         For value received        hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS OF ASSIGNEE

                  Shares of the capital stock represented by the within
Certificate, and do hereby irrevocably constitute and appoint Attorney to
transfer the said stock on the books of the within-named Corporation with full
power of substitution in the premises.

Dated

                           NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST
                           CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF
                           THE CERTIFICATE IN EVERY PARTICULAR WITHOUT
                           ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.

SIGNATURE(S) REQUIRED:

                  THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR
                  INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN
                  ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED
                  SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C.
                  RULE 17Ad-15.