ASSIGNMENT AND AMENDMENT AGREEMENT

         THIS  ASSIGNMENT  AND  AMENDMENT  dated as of  February  4, 2000  (this
"Agreement"),  made  by  and  between  Covol  Technologies,   Inc.,  a  Delaware
corporation  ("Covol"),  Utah  Synfuel #1 Ltd., a Delaware  limited  partnership
("Utah Synfuel"),  AJG Financial Services, Inc., a Delaware corporation ("AJG"),
and Coaltech No. 1 L.P., a Delaware limited partnership ("Coaltech").

                                    RECITALS

         WHEREAS,  Covol and AJG are  parties to that  certain  Debenture  dated
January 9, 1999 (the "Debenture") in the principal amount of $4,367,351.28; and

         WHEREAS,  as of the date  hereof,  the total amount owing from Covol to
AJG under the Debenture is $4,927,318.23 (the "Debenture Balance"); and

         WHEREAS,  Covol, Utah Synfuel, and Coaltech are parties to that certain
Non- Negotiable  Nonrecourse Promissory Note dated March 7, 1997 (the "Note") in
the principal amount of $3,500,000,  and that certain Security Agreement of even
date therewith (the "Security Agreement") relating to the note; and

         WHEREAS, as of the date hereof, the total amount owing from Coaltech to
Covol under the Note is $2,965,361.82 (the "Note Balance"); and

         WHEREAS, Covol and AJG desire and are willing to amend the terms of the
Debenture; and

         WHEREAS,  the  parties  hereto  desire to  effect  the  assignment  and
transfer by Covol and Utah  Synfuel to AJG of all the right,  title and interest
of Covol and Utah Synfuel in, under and with respect to the Note.

         NOW  THEREFORE,  in  consideration  of  the  premises  and  the  mutual
covenants and agreements herein contained, and for other valuable consideration,
the receipt and sufficiency of which is hereby acknowledged,  the parties hereto
do hereby agree as follows:

         SECTION 1. Assignment.


         (a) Effective as of the date hereof,  Covol and Utah Synfuel hereby (i)
irrevocably sell,  assign,  transfer and convey to AJG all of their right, title
and interest in and to the Note;  (ii) release any and all liens,  encumbrances,
and security  interests of whatsoever  nature against the Collateral (as defined
in the Note); (iii) agree that the Security Agreement is

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terminated effective as of the date hereof; and (iv) agree to execute,  deliver,
and file such documents of release of lien,  including UCC filings, as AJG shall
reasonably direct.

         (b) Covol and Utah  Synfuel  hereby  covenant  and agree to pay over to
AJG, if and when received  following the date hereof, any amounts (including any
sums payable as interest in respect thereof) paid to or for the benefit of Covol
or Utah Synfuel that, under subsection (a) hereof, belong to AJG.

         SECTION 2. Amendment.

         (a) As of the  date  hereof,  Covol  and AJG  amend  the  Debenture  as
follows: (i) the Debenture Balance is reduced by the amount of the Note Balance,
to a  remaining  balance  of  $1,939,232.04  due  from  Covol to AJG  under  the
Debenture; and (ii) the due date of the Debenture for the remaining balance plus
interest is extended  from January 10, 2000 to October 31,  2000;  and all other
terms and provisions of the Debenture  (including  terms of the letter agreement
dated 26 February  1998 by and between Covol and AJG) shall remain in full force
and effect.

         (b) The amount due and  payable on October  31,  2000 is the  remaining
balance due under the Debenture of $1,961,956.41 plus interest of $86,756.09 for
a total of $2,048,712.40.

         SECTION  3.  Governing  Law.  This  Agreement  shall be  construed  and
enforced in accordance with and governed by the law of the State of Utah without
giving effect to the principles thereof relating to conflicts of law.

         SECTION 4.  Counterparts.  This Agreement may be executed in any number
of  counterparts,  each of which shall be deemed an  original,  but all of which
together shall constitute one and the same agreement.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered on the date first above written.

                                             COVOL TECHNOLOGIES, INC.


                                             /s/ Brent M. Cook
                                             ---------------------------
                                             Name:  Brent M. Cook
                                             Title: President

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                                             AJG FINANCIAL SERVICES, INC.


                                             /s/ John C. Rosengren
                                             ---------------------
                                             Name:  John C. Rosengren
                                             Title: Vice President and
                                                    General Counsel


                                             UTAH SYNFUEL #1 LTD.

                                             By Covol Technologies, Inc.,
                                               general partner


                                             /s/ Brent M. Cook
                                             Name:  Brent M. Cook
                                             Title: President

                                             COALTECH NO. 1, L.P.
                                             By: US Coal LLC, general partner


                                             /s/ David S. O'Neill
                                             --------------------
                                             Name:  David S. O'Neill
                                             Title: Manager of the General
                                                    Partner

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