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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We consent to the incorporation by reference in this Post-Effective Amendment No. 1 to Registration Statement No. 333-117183 of Quanex Corporation on Form S-3 of our report dated December 21, 2004, appearing in the Annual Report on Form 10-K of Quanex Corporation for the year ended October 31, 2004, and to the reference to us under the heading "Experts" which is part of this Registration Statement.

DELOITTE & TOUCHE LLP

Houston, Texas
January 6, 2005

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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM