<PAGE>





                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549


                                    FORM 10-Q/A


(Mark One)
/X/        QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
           EXCHANGE ACT OF 1934
           For the quarterly period ended April 30, 1999

                                       OR

/ /        TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
           SECURITIES EXCHANGE ACT OF 1934

           For the transition period from _______ to _______



                         COMMISSION FILE NUMBER 333-4513


                               RENCO METALS, INC.
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                                     <C>
                DELAWARE                                    13-3724916
     (State or other jurisdiction of                       (IRS Employer
     incorporation or organization)                     Identification No.)

           238 NORTH 2200 WEST
          SALT LAKE CITY, UTAH                                  84116
  (Address of principal executive offices)                   (Zip Code)
</TABLE>

                                 (801) 532-2043
              (Registrant's telephone number, including area code)



Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports) and (2) has been subject to such filing
requirements for the past 90 days.
                                                      / / YES        /X/   NO


Number of shares outstanding of each of the registrant's classes of common
stock, as of June 14, 1999:

COMMON STOCK, NO PAR VALUE                                   1,000 SHARES


<PAGE>

Preliminary Note: This amendment is filed to correct the long-term debt
figures in the balance sheets.


                         PART I - FINANCIAL INFORMATION

ITEM 1 - FINANCIAL STATEMENTS



                      RENCO METALS, INC. AND SUBSIDIARIES
                     CONDENSED CONSOLIDATED BALANCE SHEETS
                (DOLLARS IN THOUSANDS, EXCEPT PER SHARE AMOUNTS)

<TABLE>
<CAPTION>

                                                                                   APRIL 30,       OCTOBER 31,
                                                                                     1999             1998
                                     ASSETS                                       (UNAUDITED)       (AUDITED)
                                                                                 -------------    -------------
<S>                                                                                  <C>              <C>
Current assets:
      Cash and cash equivalents                                                      $ 15,885         $ 21,690
      Accounts receivable, less allowance for doubtful accounts of
         $589 in 1999 and $514 in 1998                                                 24,543           25,749
      Inventories, net (note 2)                                                        42,713           34,500
      Prepaid expenses and other current assets                                         3,438            3,024
                                                                                 -------------    -------------
                  Total current assets                                                 86,579           84,963
                                                                                 -------------    -------------
Property, plant, and equipment, net                                                    37,012           35,385
Other assets, net                                                                       5,306            5,626
                                                                                 -------------    -------------
                                                                                     $128,897        $ 125,974
                                                                                 -------------    -------------
                                                                                 -------------    -------------

                     LIABILITIES AND STOCKHOLDER'S DEFICIT
Current liabilities:
      Current installments of long-term debt                                         $     23        $      23
      Accounts payable                                                                  7,491            7,279
      Accrued expenses and other current liabilities                                   14,442           15,149
                                                                                 -------------    -------------
                  Total current liabilities                                            21,956           22,451
                                                                                 -------------    -------------
Long-term debt, excluding current installments                                        154,567          154,954
Other liabilities                                                                      12,506           14,180
                                                                                 -------------    -------------
                  Total liabilities                                                   189,029          191,585
                                                                                 -------------    -------------
Stockholder's deficit:
      Common stock, no par value.  Authorized, issued, and
         outstanding 1,000 shares                                                           1                1
      Additional paid-in capital                                                          500              500
      Accumulated deficit                                                             (60,633)         (66,112)
                                                                                 -------------    -------------
                  Total stockholder's deficit                                         (60,132)         (65,611)
                                                                                 -------------    -------------
Commitments and contingencies
                                                                                 -------------    -------------
                                                                                     $128,897        $ 125,974
                                                                                 -------------    -------------
                                                                                 -------------    -------------

</TABLE>


  The accompanying notes are an integral part of these condensed consolidated
                       financial statements.


<PAGE>



                  RENCO METALS, INC. AND SUBSIDIARIES
              CONDENSED CONSOLIDATED STATEMENTS OF INCOME
                             (UNAUDITED)
                        (DOLLARS IN THOUSANDS)

<TABLE>
<CAPTION>

                                                               SIX MONTHS                   THREE MONTHS
                                                             ENDED APRIL 30,               ENDED APRIL 30,
                                                       ---------------------------   ---------------------------
                                                           1999           1998           1999           1998
                                                       ------------   ------------   ------------   ------------
<S>                                                       <C>            <C>            <C>            <C>
Sales                                                     $ 87,567       $ 94,964       $ 45,947       $ 47,545
Costs and expenses:
      Cost of sales                                         60,313         60,540         31,545         29,606
      Depreciation, depletion, and amortization              4,672          4,406          2,336          2,130
      Selling, general, and administrative expenses         10,199         12,042          5,520          6,876
                                                       ------------   ------------   ------------   ------------
                  Total costs and expenses                  75,184         76,988         39,401         38,612
                                                       ------------   ------------   ------------   ------------
                     Income from operations                 12,383         17,976          6,546          8,933

Other income (expense):
      Interest income                                          363            585            124            269
      Interest expense                                      (9,330)        (9,450)        (4,659)        (4,730)
                                                       ------------   ------------   ------------   ------------
                  Total other income (expense)              (8,967)        (8,865)        (4,535)        (4,461)
                                                       ------------   ------------   ------------   ------------
                     Income before income taxes              3,416          9,111          2,011          4,472
Income tax (benefit) expense (note 3)                       (2,063)         2,720              -          1,358
                                                       ------------   ------------   ------------   ------------
                         Net income                        $ 5,479        $ 6,391        $ 2,011        $ 3,114
                                                       ------------   ------------   ------------   ------------
                                                       ------------   ------------   ------------   ------------
</TABLE>



   The accompanying notes are an integral part of these condensed consolidated
                           financial statements.


<PAGE>



                    RENCO METALS, INC. AND SUBSIDIARIES
               CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
                              (UNAUDITED)
                        (DOLLARS IN THOUSANDS)

<TABLE>
<CAPTION>

                                                                                          SIX MONTHS
                                                                                        ENDED APRIL 30,
                                                                                  ---------------------------
                                                                                      1999           1998
                                                                                  ------------    -----------
<S>                                                                                    <C>           <C>
Net cash provided by operating activities                                              $  899        $ 2,875
                                                                                  ------------    -----------
Cash flows from investing activities -
      Capital expenditures, net                                                        (6,268)        (1,769)
                                                                                  ------------    -----------
                  Net cash used in investing activities                                (6,268)        (1,769)
                                                                                  ------------    -----------
Cash flows from financing activities:
      Net borrowings (repayments) under revolving credit agreements                      (375)         1,752
      Repayment of long-term debt                                                         (11)           (10)
      Payment of financing fees                                                           (50)             -
      Dividends                                                                             -         (2,000)
                                                                                  ------------    -----------
                  Net cash used in financing activities                                  (436)          (258)
                                                                                  ------------    -----------
Increase (decrease) in cash and cash equivalents                                       (5,805)           848
Cash and cash equivalents, beginning of period                                         21,690         26,607
                                                                                  ------------    -----------
Cash and cash equivalents, end of period                                             $ 15,885       $ 27,455
                                                                                  ------------    -----------
                                                                                  ------------    -----------

SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
      Cash paid during the period for interest                                       $  8,836       $  8,956
      Cash paid during the period for income taxes                                   $    209       $  3,016
</TABLE>


   The accompanying notes are an integral part of these condensed consolidated
                           financial statements.


<PAGE>


                       RENCO METALS, INC. AND SUBSIDIARIES
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                                   (UNAUDITED)


(1)    BASIS OF PRESENTATION

       The accompanying condensed consolidated financial statements have been
       prepared from the accounting records of Renco Metals, Inc. (Renco Metals)
       and its subsidiaries (the Company), Magnesium Corporation of America
       (Magcorp), and Sabel Industries, Inc. (Sabel), without audit (except
       where presented data is specifically identified as audited) pursuant to
       the rules and regulations of the Securities and Exchange Commission.
       Renco Metals is a 100% owned subsidiary of The Renco Group, Inc. (Group).
       The financial statements reflect all adjustments (consisting solely of
       normal recurring adjustments) which are, in the opinion of management,
       necessary for a fair statement of results for the interim periods
       presented. The results of operations for the interim periods presented
       are not necessarily indicative of the results to be expected for the full
       year. These interim condensed consolidated financial statements should be
       read in conjunction with the consolidated financial statements and notes
       thereto included in the Company's Form 10-K for the fiscal year ended
       October 31, 1998.

       Renco Metals' 11.5% Senior Notes due 2003 (Senior Notes) are
       unconditionally and fully guaranteed, jointly and severally, by both of
       its subsidiaries, Magcorp and Sabel (the Guarantors), each of which is
       wholly-owned. Separate financial statements of the Guarantors are not
       presented because, in management's opinion, such financial statements
       would not be material to investors because Renco Metals is a holding
       company with no independent operations and its only assets are cash and
       its investment in Magcorp and Sabel. Summarized financial information on
       the combined Guarantors is presented below:

             SUMMARIZED COMBINED GUARANTOR FINANCIAL INFORMATION

<TABLE>
<CAPTION>

                                                SIX MONTHS                     THREE MONTHS
                                              ENDED APRIL 30,                 ENDED APRIL 30,
                                            1999          1998              1999           1998
                                         ------------  ------------     --------------  ------------
                                          (DOLLARS IN THOUSANDS)          (DOLLARS IN THOUSANDS)
<S>                                          <C>           <C>               <C>            <C>
Statement of operations data:
       Net sales                             $87,567       $94,964           $ 45,947       $47,545
       Cost of sales                         $60,313       $60,540           $ 31,545       $29,606
       Net income                            $ 5,422       $ 6,379           $  1,972       $ 3,103

</TABLE>

<TABLE>
<CAPTION>

                                                                                        OCTOBER 31,
                                                                          APRIL 30,        1998
                                                                            1999         (AUDITED)
                                                                        --------------  ------------
                                                                           (DOLLARS IN THOUSANDS)
<S>                                                                          <C>            <C>
Balance sheet data:
       Current assets                                                        $ 84,752       $83,687
       Noncurrent assets                                                     $ 42,318       $41,011
       Current liabilities                                                   $ 15,311       $16,300
       Noncurrent liabilities                                                $ 17,073       $19,134

</TABLE>


<PAGE>


(2)    INVENTORIES

       Inventories consist of the following:

<TABLE>
<CAPTION>

                                                                     APRIL 30,       OCTOBER 31,
                                                                        1999            1998
                                                                    (UNAUDITED)       (AUDITED)
                                                                   --------------   -------------
                                                                       (DOLLARS IN THOUSANDS)
<S>                                                                     <C>              <C>
       Finished goods                                                   $  32,513        $ 24,451
       Brine in ponds                                                       1,117           1,100
       Spare parts and supplies                                             8,859           8,740
       Raw materials and work-in-process                                    1,146             743
                                                                   ---------------  --------------
                                                                           43,635          35,034
       Less LIFO reserve                                                      922             534
                                                                   ---------------  --------------
                                                                        $  42,713        $ 34,500
                                                                   ---------------  --------------
                                                                   ---------------  --------------
</TABLE>


(3)    INCOME TAXES

       On January 15, 1999, Group filed an election with the consent of its
       shareholders with the Internal Revenue Service to change its taxable
       status from that of a subchapter C corporation to that of a subchapter
       S corporation, effective November 1, 1998. At the same time, Group
       elected for the Company to be treated as a qualified subchapter S
       subsidiary (QSSS). Most states in which the Company operates will follow
       similar tax treatment. QSSS status requires the ultimate shareholders to
       include their pro rata share of the Company's income or loss in their
       individual tax returns. The Company will continue to provide for state
       and local income taxes for the taxing jurisdictions which do not
       recognize QSSS status; however, management believes this is not material
       to the Company. As a result of this change in tax status, the Company
       recognized an income tax benefit of $2,063,000 during the three months
       ended January 31, 1999, which included the elimination of net deferred
       tax liabilities recorded as of October 31, 1998.

<PAGE>


                               S I G N A T U R E S


        Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                                    RENCO METALS, INC.
                                                    (Registrant)



<TABLE>
<S>                                                 <C>

         JUNE 14, 1999                                /s/  IRA LEON RENNERT
--------------------------                          -----------------------------
Date                                                Ira Leon Rennert
                                                    Chairman of the Board and
                                                    Principal Executive Officer



         JUNE 14, 1999                                /s/  ROGER L. FAY
--------------------------                          -----------------------------
Date                                                Roger L. Fay
                                                    Vice President - Finance
                                                    Principal Financial  and
                                                    Accounting Officer
</TABLE>