EXHIBIT 99.4

                        WARRANTS TO PURCHASE COMMON STOCK
                                       OF
                             OGLEBAY NORTON COMPANY
                   PURSUANT TO THE PROSPECTUS DESCRIBED BELOW
             AND THE SECOND AMENDED JOINT PLAN OF REORGANIZATION OF
               ONCO INVESTMENT COMPANY, OGLEBAY NORTON COMPANY AND
                    CERTAIN SUBSIDIARIES DATED JULY 30, 2004

               THE EXERCISE PERIOD FOR THE WARRANTS WILL EXPIRE AT
   5:00 P.M., EASTERN TIME, ON [_________ __], 2005 (THE "EXPIRATION DATE").

                                                               [______ __], 2005

To Our Clients:

      Enclosed for your consideration, among other documents, is a Prospectus
dated [_______ __], 200[_] (together with any amendments or supplements thereto,
the "Prospectus") relating to the issuance and distribution by reorganized
Oglebay Norton Company ("Reorganized Oglebay") to holders of record of shares of
common stock ("Old Common Stock") of Oglebay Norton Company before
reorganization ("Oglebay") as of the close of business on November 17, 2004 (the
"Distribution Record Date") of warrants (the "Warrants") (CUSIP No. 677007 11 4)
to acquire shares of common stock of Reorganized Oglebay (the "New Common
Stock") (CUSIP No. 677007 20 5) in accordance with the terms of the Second
Amended Joint Plan of Reorganization of ONCO Investment Company, Oglebay and
Certain Subsidiaries, dated July 30, 2004 (as further amended or modified, the
"Plan"), which was confirmed by an order of the United States Bankruptcy Court
for the District of Delaware entered on November 17, 2004. Reorganized Oglebay
emerged from bankruptcy on [__________ __], 2005 (the "Effective Date"). Under
the Plan, on the Effective Date, certificates formerly representing shares of
Old Common Stock were cancelled, and each record holder of Old Common Stock on
the Distribution Record Date received one Warrant for each share of Old Common
Stock then held. Each Warrant represents the right to purchase one-tenth
(1/10th) of a fully paid and nonassessable share of New Common Stock. The
Warrants are exercisable at an exercise price of $10.00 per share of New Common
Stock (the "Exercise Price"). The Warrants entitle the holder thereof to
purchase at the Exercise Price one share of New Common Stock for each ten (10)
Warrants held. Except in the case where a holder of Warrants is exercising all
Warrants then held, shares of New Common Stock may be purchased only pursuant to
the exercise of Warrants in integral multiples of ten (10). Reorganized Oglebay
will not issue any fractional shares of New Common Stock upon the exercise of
the Warrants. If any fraction of a share of New Common Stock would be issuable
upon the exercise of all Warrants then held by a holder of Warrants, such
Warrant exercise will be rounded to the nearest whole share (up or down), with
half shares being rounded up. The Warrants are transferable; provided, however,
that any Warrants held by an affiliate of Reorganized Oglebay may generally only
be resold pursuant to a valid exemption under the Securities Act of 1933. The
Warrants are exercisable by subsequent holders thereof subject to certain
conditions.


      The Warrants may only be exercised by us and only pursuant to your
instructions. Accordingly, we request instructions as to whether you wish us to
exercise the Warrants for your account.










      WE ENCOURAGE YOU TO READ THE ENCLOSED DOCUMENTS CAREFULLY BEFORE
INSTRUCTING US TO EXERCISE THE WARRANTS ON YOUR BEHALF.

      Please note the following:

      1.    The Warrants permits us, for your account, to purchase a number of
            shares of New Common Stock.

      2.    The Exercise Price of the Warrants is $10.00 per share of New Common
            Stock.

      3.    The Warrants will expire at 5:00 p.m., Eastern time, on the
            Expiration Date.

      4.    The Warrants are transferable; provided, however, that any Warrants
            held by an affiliate of Reorganized Oglebay may generally only be
            resold pursuant to a valid exemption under the Securities Act of
            1933.





      Your instructions, and payment in full of an amount equal to the Exercise
Price multiplied by the number of shares of New Common Stock (the "Exercise
Amount") purchased by us for your account pursuant to the Warrants, should be
forwarded to us as promptly as possible to permit us to exercise the Warrants on
your behalf on the terms and subject to the conditions described in the
Prospectus and the other enclosed materials. The exercise of the Warrants cannot
be revoked.



      If you wish to have us, on your behalf, exercise the Warrants for your
account, please so instruct us by completing, executing, detaching and returning
to us the instruction form set forth on the detachable part of this letter,
together with payment in full of the Exercise Amount. If we do not receive
complete written instructions in accordance with the procedures outlined in the
Prospectus and the other enclosed materials, together with payment of the
Exercise Amount as described above, we will not exercise the Warrants for your
account.


      Any questions or request for assistance concerning the exercise or
transfer of the Warrants should be directed to Wells Fargo Bank, N.A., by
telephone at (800) 344-5128 or (612) 667-9764, by fax at (612) 667-6282 or in
writing as follows:



Registered and Certified Mail:           Regular Mail or Courier:             In Person by Hand Only:
- -----------------------------            -----------------------              ----------------------
                                                                        
Wells Fargo Bank, N.A.                   Wells Fargo Bank, N.A.               Wells Fargo Bank, N.A.
Corporate Trust Operations               Corporate Trust Operations           Corporate Trust Services
MAC N9303-121                            MAC N9303-121                        Northstar East Bldg-12th Floor
P.O. Box 1517                            6th & Marquette Avenue               608 2nd Avenue South
Minneapolis, MN 55480                    Minneapolis, MN 55479                Minneapolis, MN 55402


                                     - 2 -



                                BENEFICIAL OWNER
                              ELECTION INSTRUCTIONS


      The undersigned acknowledge(s) receipt of your letter and the enclosed
materials referred to therein relating to the opportunity to purchase
post-reorganization shares of common stock, par value of $0.01 ("Common Stock")
of Oglebay Norton Company (the "Company") through the exercise of warrants (the
"Warrants") at a purchase price of $10.00 per share of Common Stock on the terms
and subject to the conditions set forth in the Prospectus of the Company and the
other enclosed materials.


      This will instruct you whether to exercise the Warrants to purchase shares
of Common Stock for the account of the undersigned and, if the undersigned
elects to exercise the Warrants, the number of shares of Common Stock to be
purchased for the account of the undersigned.

    [ ]  Please DO NOT EXERCISE THE WARRANTS for Common Stock.

    [ ]  Please EXERCISE THE WARRANTS for Common Stock as set forth below.


                                             
Number of Warrants to be exercised
                                                --------------------

Number of Share(s) of Common Stock
           to be purchased
                                                --------------------

           Exercise Price                     x $    10.00 per share
                                                --------------------
           Total Payment Required               $
                                                ====================


    [ ]  Payment in the following amount is enclosed:  $______________________

    [ ]  Please deduct payment from the following account maintained by you as
         follows:

        ______________________________              ___________________________
               Type of Account                               Account No.

                  Amount to be deducted: $____________________

PLEASE SIGN AND DATE HERE:

Date: ______________________                            _______________________
                                                              Signature(s)

                                                        _______________________
                                                          Please print name(s)