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                                                                 Exhibit 10.1

                      MODIFICATION AND EXTENSION AGREEMENT


         THIS MODIFICATION AND EXTENSION AGREEMENT ("Agreement") is executed as
of the 30th day of September, 1997, by and among 19th Avenue/Buchanan Limited
Partnership, an Arizona Limited Partnership ("19th Avenue") and Schuff Steel
Company, a Delaware Corporation ("Schuff Steel").


                                    RECITALS

         A. Schuff Steel as Maker owes the sum of ONE MILLION EIGHT HUNDRED
THIRTY THOUSAND SEVEN HUNDRED FIFTY-SEVEN DOLLARS AND SIXTEEN CENTS
($1,830,757.16) as of September 30, 1997 to 19th Avenue pursuant to that
certain Promissory Note dated December 31, 1989 in the original principal
balance of FOUR MILLION TWO HUNDRED FORTY-NINE THOUSAND SIXTY-TWO DOLLARS
($4,249,062,00), a copy of which is attached hereto as Exhibit "A" (hereinafter
referred to as the "Note").

         B. The maturity date of the Note was extended and modified from May
31, 1994 to May 31, 1999 in accordance with that certain Modification and
Extension Agreement and Affirmation of Guaranties dated February 23, 1993, a
copy of which is attached hereto as Exhibit "B" (hereinafter referred to as the
"Extension").

         C. Schuff Steel desires to modify and extend the Note and 19th Avenue
is willing to do so.

         D. The parties hereto are desirous of entering into this Agreement and
modifying the Note in accordance with the terms and conditions set forth herein.


                                   AGREEMENT

         NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, included but not limited to, the
Recitals above, the parties hereto agree as follows:

         1. Maturity Date Extension.

         a. 19th Avenue and Schuff Steel agree that the maturity date of the
Note ("Maturity" therein), as defined and modified in paragraph 1(b) of the
Extension, is hereby extended and modified from May 31, 1999 to April 30, 2003.

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     2. Interest Payment. Commencing on October 1, 1997, the Note shall bear
interest on the unpaid balance outstanding at an annual rate of 3/4 (.75)
percentage points above the interest rate announced by Bank One from time to
time as its prime interest rate, which interest payments shall be paid monthly
on the last day of each and every month until Maturity.

     3. Principal Payments. Principal payments under the Note shall continue to
be paid in monthly principal payments of TWELVE THOUSAND THIRTY-SEVEN DOLLARS
($12,037.00) which payments shall continue until Maturity, at which time all
remaining unpaid principal and interest, and all other amounts payable under
the Note shall be paid in full.

     4. Unpaid Balance. The parties hereto acknowledge and agree that there are
no claims or offsets against the current unpaid principal balance of the Note.

     5. Status of Note and Deed of Trust. This Agreement constitutes a
modification of the Note and the Extension, as previously modified, only with
respect to all matters set forth herein. All of the other terms, covenants,
conditions and agreements contained in the Note and the Extension, as
previously modified, shall remain in full force and effect. This Agreement
shall not release Schuff Steel from any liability under the Note.

     6. Binding Effect. This Agreement represents the complete understanding
and entire agreement of the parties as to the subject matter contained herein,
and may not be amended except by a writing executed by both parties. This
Agreement shall be binding upon and inure to the benefit of the respective
heirs, successors and assigns of each of the parties hereto.

     7. Time of the Essence. Time is of the essence for the performance by
Schuff Steel of each of its obligations under the Note.

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

     9. Severability. In the event any one or more of the provisions of this
Agreement or the Note are held to be invalid, illegal or unenforceable in any
respect by any court or other entity having the authority to do so, the
validity of the remaining provisions hereof and thereof shall in no way be
affected, prejudiced, or disturbed.

     10. Miscellaneous. The titles of the paragraphs hereof are for reference
purposes only and do not constitute part of this Agreement. This Agreement
shall be construed in accordance with and governed by the laws of the State of
Arizona.

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19th Avenue/Buchanan
Limited Partnership, an Arizona
Limited Partnership


By: /s/ David A. Schuff
    ------------------------
        David A. Schuff
        General Partner

By: /s/ Nancy A. Schuff
    ------------------------
        Nancy A. Schuff
        General Partner

By: /s/ Scott A. Schuff
    ------------------------
        Scott A. Schuff
        General Partner

Schuff Steel Company, a Delaware
Corporation

By: /s/ Scott A. Schuff
    ------------------------
        Scott A. Schuff, President


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