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                                                                  EXHIBIT 10.4.8

           SEVENTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

         THIS SEVENTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT
(hereinafter referred to as the "Amendment") executed as of the 23rd day of
December, 2003, by and among RANGE RESOURCES CORPORATION, a Delaware corporation
("Borrower"), BANK ONE, NA, a national banking association ("Bank One"), each of
the financial institutions which is a party hereto (as evidenced by the
signature pages to this Amendment) or which may from time to time become a party
hereto pursuant to the provisions of Section 29 of the Credit Agreement or any
successor or assignee thereof (hereinafter collectively referred to as
"Lenders", and individually, "Lender"), Bank One, as Administrative Agent
("Agent"), Fleet National Bank, as Co-Documentation Agent, Fortis Capital Corp.,
as Co-Documentation Agent, JPMorgan Chase Bank, as Co-Syndication Agent, Credit
Lyonnais New York Branch, as Co-Syndication Agent, Banc One Capital Markets,
Inc., as Joint Lead Arranger and Joint Bookrunner and JPMorgan Securities, Inc.,
as Joint Lead Arranger and Joint Bookrunner. Capitalized terms used but not
defined in this Amendment have the meanings assigned to such terms in that
certain Amended and Restated Credit Agreement dated as of May 2, 2002, by and
among Borrower, Agent and Lenders (as amended, supplemented or otherwise
modified from time to time, the "Credit Agreement").

                                   WITNESSETH:

         WHEREAS, the Borrower has informed Agent and Lenders that the
Borrower's wholly-owned Subsidiary, Range Production I, L.P., a Texas limited
partnership ("Range Production I") intends to acquire certain oil and gas
properties of Wagner & Brown, Ltd., a Texas limited partnership ("Wagner
Brown"), Canyon Energy Partners, Ltd., a Texas limited partnership ("Canyon
Energy") and Intercon Gas, Inc., a Delaware corporation ("Intercon") pursuant to
that certain Purchase and Sale Agreement dated as of December 13, 2003, among
Range Production I, Wagner Brown, Canyon Energy and Intercon (the "Sterling
Acquisition");

         WHEREAS, in connection with the Sterling Acquisition, the Borrower has
requested that the Agent and the Lenders amend the Credit Agreement to (i)
increase the Borrowing Base to $225,000,000 and (ii) allow the Borrower to sell,
lease, transfer or otherwise dispose of Oil and Gas Properties in an aggregate
amount not to exceed $25,000,000 during the period beginning on the Sterling
Acquisition Closing Date (as hereinafter defined) and ending the next
Determination Date; and Agent and the Lenders have agreed to do so on the terms
and conditions hereinafter set forth.

         NOW, THEREFORE, for and in consideration of the mutual covenants and
agreements herein contained and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged and confessed, the
Borrower, Agent and the Lenders, hereby agree as follows:

SECTION 1. AMENDMENTS TO CREDIT AGREEMENT. Subject to the satisfaction or waiver
in writing of each condition precedent set forth in Section 3 hereof, and in
reliance on the

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representations, warranties, covenants and agreements contained in this
Amendment, the Credit Agreement shall be amended in the manner provided in this
Section 1.

         1.1      DEFINITIONS. The definition of "Guarantor" set forth in
Section 1 of the Credit Agreement shall be and it hereby is amended in its
entirety as follows:

         Guarantor means GulfStar Energy, Inc., Range Energy I, Inc., Range
HoldCo, Inc., Range Production Company, Range Energy Ventures Corporation, Range
Energy Finance Corporation, Range Production I, L.P. and Range Resources, L.L.C.

         1.2      ADDITIONAL DEFINITIONS. Section 1 of the Credit Agreement
shall be and it hereby is amended by inserting the following definitions in
alphabetical order:

         Range Production I means Range Production I, L.P., a Texas limited
partnership.

         Sterling Acquisition means the acquisition by Range Production I of
certain oil and gas properties of the Sterling Acquisition Sellers pursuant to
the Sterling Acquisition Purchase Agreement.

         Sterling Acquisition Closing Date means the date on which the Sterling
Acquisition is consummated in accordance with the terms of the Sterling
Acquisition Purchase Agreement.

         Sterling Acquisition Purchase Agreement means that certain Purchase and
Sale Agreement dated as of December 13, 2003, among Borrower's wholly-owned
Subsidiary, Range Production I and the Sterling Acquisition Sellers, as amended,
modified or restated from time to time.

         Sterling Acquisition Sellers means, collectively, Wagner & Brown, Ltd.,
a Texas limited partnership, Canyon Energy Partners, Ltd., a Texas limited
partnership and Intercon Gas, Inc., a Delaware corporation.

         1.3      AMENDMENT TO BORROWING BASE. Section 7(a) of the Credit
Agreement shall be and it hereby is amended in its entirety to read as follows:

                  (a)      Initial Borrowing Base. Subject to Section 7(b)
         hereof, (i) as of October 1, 2003, the Borrowing Base shall be
         $180,000,000 and (ii) as of the Sterling Acquisition Closing Date, the
         Borrowing Base shall be $225,000,000.

         1.4      SALE OF CERTAIN ASSETS. The first sentence of Section 12(r) of
the Credit Agreement shall be and it is hereby amended in its entirety to read
as follows:

Borrower will immediately pay over to the Agent for the ratable benefit of the
Lenders as a prepayment of principal on the Notes and a reduction of the
Commitments, an amount equal to 100% of the "Release Price" from the sale of Oil
and Gas Properties by Borrower or any Guarantor in excess of $10,000,000 (except
that during the period beginning on the Sterling Acquisition Closing Date and
ending on the next Determination Date, such amount shall be

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100% of the "Release Price" from the sale of Oil and Gas Properties by Borrower
or any Guarantor in excess of $25,000,000) in the aggregate received from such
sales between Borrowing Base redeterminations, which sale has been either (i)
made in compliance with the provisions of Section 13(a)(ii) hereof, or (ii)
approved in advance by Required Lenders. Provided, however, that in lieu of
making any such payment the Borrower may elect to provide, or cause to be
provided by a Guarantor, additional Oil and Gas Properties with value and
quality satisfactory to all Lenders in their discretion in substitution for the
Oil and Gas Properties sold pursuant to the provisions of this Section 12(r).

         1.5      NEGATIVE PLEDGE. Clause B of Section 13(a)(ii) of the Credit
Agreement shall be and it is hereby amended in its entirety to read as follows:

(B) sales, leases, transfers or other dispositions of Oil and Gas Properties
which do not exceed $10,000,000 in the aggregate between Borrowing Base
redeterminations; provided that during the period beginning on the Sterling
Acquisition Closing Date and ending on the next Determination Date, such sales,
leases, transfers or other dispositions of Oil and Gas Properties shall not
exceed $25,000,000;

         1.6      AMENDMENT TO EXHIBIT. Exhibit B to the Credit Agreement shall
be and is hereby amended in its entirety by substituting Exhibit B which is
attached hereto.

         1.7      ASSIGNMENT AND ACCEPTANCE. The Lenders have agreed among
themselves to reallocate their respective Commitments and to allow Hibernia
National Bank and Southwest Bank of Texas, N.A. to acquire an interest in the
Commitments and the Loans. After such reallocation of the Commitments, on the
date hereof, the Lenders shall own the Commitment Percentages set forth on
Schedule 1 attached hereto. With respect to such reallocation, each of Hibernia
National Bank and Southwest Bank of Texas, N.A. shall be deemed to have acquired
the Commitments and Loans allocated to them from each of the Lenders pursuant to
the terms of the Assignment and Acceptance Agreement attached as Exhibit E to
the Credit Agreement as if Hibernia National Bank, Southwest Bank of Texas, N.A.
and the Lenders had executed an Assignment and Acceptance Agreement with respect
to such allocation. Each Lender shall surrender its existing Note and be issued
a new Note in a face amount equal to each Lender's Commitment Percentage times
$225,000,000. Each said Note to be in the form of Exhibit "B" to the Credit
Agreement with appropriate insertions. The funds delivered to Agent by Hibernia
National Bank and Southwest Bank of Texas, N.A. to acquire an interest in the
Commitments and the Loans shall be allocated and paid to each of the existing
Lenders such that after giving effect to such allocation and payment each of the
Lender's Commitment shall be in the amounts set forth on Schedule 1 attached
hereto.

SECTION 2. REAFFIRMATION OF REPRESENTATIONS AND WARRANTIES. Except to the extent
its provisions are specifically amended, modified or superseded by this
Amendment, the representations, warranties and affirmative and negative
covenants of the Borrower contained in the Credit Agreement are incorporated
herein by reference for all purposes as if copied herein in full. The Borrower
hereby restates and reaffirms each and every term and provision of the Credit
Agreement, as amended, including, without limitation, all representations,
warranties and affirmative and negative covenants. Except to the extent its
provisions are specifically amended,

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modified or superseded by this Amendment, the Credit Agreement, as amended, and
all terms and provisions thereof shall remain in full force and effect, and the
same in all respects are confirmed and approved by the Borrower and the Lenders.

SECTION 3. CONDITIONS. The amendments to the Credit Agreement contained in
Section 1 of this Amendment shall be effective upon the satisfaction of each of
the conditions set forth in this Section 3.

         3.1      EXECUTION AND DELIVERY. The Borrower and each Guarantor shall
have executed and delivered this Amendment, and other required documents, all in
form and substance satisfactory to the Agent.

         3.2      REPRESENTATIONS AND WARRANTIES. The representations and
warranties of the Borrower under this Amendment are true and correct in all
material respects as of such date, as if then made (except to the extent that
such representations and warranties related solely to an earlier date).

         3.3      NO EVENT OF DEFAULT. No Event of Default shall have occurred
and be continuing nor shall any event have occurred or failed to occur which,
with the passage of time or service of notice, or both, would constitute an
Event of Default.

         3.4      OTHER DOCUMENTS. The Agent shall have received (i) a duly
executed officer's certificate of Borrower, together with true and correct
copies of the amended and restated bylaws of Borrower, and (ii) such other
instruments and documents incidental and appropriate to the transaction provided
for herein as the Agent or its counsel may reasonably request, and all such
documents shall be in form and substance satisfactory to the Agent.

         3.5      LEGAL MATTERS SATISFACTORY. All legal matters incident to the
consummation of the transactions contemplated hereby shall be reasonably
satisfactory to special counsel for the Agent retained at the expense of
Borrower.

SECTION 4. MISCELLANEOUS.

         4.1      ADDITIONAL REPRESENTATIONS AND WARRANTIES. Borrower hereby
represents and warrants that all factual information, if any, heretofore and
contemporaneously furnished by or on behalf of Borrower to Agent for purposes of
or in connection with this Amendment does not contain any untrue statement of a
material fact or omit to state any material fact necessary to keep the
statements contained herein or therein from being misleading. Each of the
foregoing representations and warranties shall constitute a representation and
warranty of Borrower made under the Credit Agreement, and it shall be an Event
of Default if any such representation and warranty shall prove to have been
incorrect or false in any material respect at the time given. Each of the
representations and warranties made under the Credit Agreement (including those
made herein) shall survive and not be waived by the execution and delivery of
this Amendment or any investigation by Lenders.

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         4.2      INDEMNIFICATION. The Borrower agrees to indemnify and hold
harmless the Lenders and their respective officers, employees, agents, attorneys
and representatives (singularly, an "Indemnified Party", and collectively, the
"Indemnified Parties") from and against any loss, cost, liability, damage or
expense (including the reasonable fees and out-of-pocket expenses of counsel to
the Lender, including all local counsel hired by such counsel) ("Claim")
incurred by the Lenders in investigating or preparing for, defending against, or
providing evidence, producing documents or taking any other action in respect of
any commenced or threatened litigation, administrative proceeding or
investigation under any federal securities law, federal or state environmental
law, or any other statute of any jurisdiction, or any regulation, or at common
law or otherwise, which is alleged to arise out of or is based upon any acts,
practices or omissions or alleged acts, practices or omissions of the Borrower
or its agents or arises in connection with the duties, obligations or
performance of the Indemnified Parties in negotiating, preparing, executing,
accepting, keeping, completing, countersigning, issuing, selling, delivering,
releasing, assigning, handling, certifying, processing or receiving or taking
any other action with respect to the Loan Documents and all documents, items and
materials contemplated thereby even if any of the foregoing arises out of an
Indemnified Party's ordinary negligence. The indemnity set forth herein shall be
in addition to any other obligations or liabilities of the Borrower to the
Lenders hereunder or at common law or otherwise, and shall survive any
termination of this Amendment, the expiration of the Loan and the payment of all
indebtedness of the Borrower to the Lenders hereunder and under the Notes,
provided that the Borrower shall have no obligation under this section to the
Lenders with respect to any of the foregoing arising out of the gross negligence
or willful misconduct of the Lenders. If any Claim is asserted against any
Indemnified Party, the Indemnified Party shall endeavor to notify the Borrower
of such Claim (but failure to do so shall not affect the indemnification herein
made except to the extent of the actual harm caused by such failure). The
Indemnified Party shall have the right to employ, at the Borrower's expense,
counsel of the Indemnified Parties' choosing and to control the defense of the
Claim. The Borrower may at its own expense also participate in the defense of
any Claim. Each Indemnified Party may employ separate counsel in connection with
any Claim to the extent such Indemnified Party believes it reasonably prudent to
protect such Indemnified Party. THE PARTIES INTEND FOR THE PROVISIONS OF THIS
SECTION TO APPLY TO AND PROTECT EACH INDEMNIFIED PARTY FROM THE CONSEQUENCES OF
STRICT LIABILITY IMPOSED OR THREATENED TO BE IMPOSED ON ANY INDEMNIFIED PARTY AS
WELL AS FROM THE CONSEQUENCES OF ITS OWN NEGLIGENCE, WHETHER OR NOT THAT
NEGLIGENCE IS THE SOLE, CONTRIBUTING, OR CONCURRING CAUSE OF ANY CLAIM, BUT NOT
FROM ANY PORTION OF SUCH CLAIM ARISING FROM THE GROSS NEGLIGENCE OR WILLFUL
MISCONDUCT OF ANY INDEMNIFIED PARTY.

         4.3      COUNTERPARTS. This Amendment may be executed in one or more
counterparts and by different parties hereto in separate counterparts each of
which when so executed and delivered shall be deemed an original, but all such
counterparts together shall constitute but one and the same instrument;
signature pages may be detached from multiple separate counterparts and attached
to a single counterpart so that all signature pages are physically attached to
the same document. However, this Amendment shall bind no party until Borrower,
Agent and Lenders have executed a counterpart. Facsimiles shall be effective as
originals.

         4.4      WRITTEN CREDIT AGREEMENT. THE CREDIT AGREEMENT, AS AMENDED,
REPRESENTS THE FINAL AGREEMENT BETWEEN AND AMONG THE

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PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR
SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL
AGREEMENTS BETWEEN AND AMONG THE PARTIES.

         4.5      NO IMPAIRMENT. Borrower acknowledges and agrees that the
renewal, extension and amendment of the Credit Agreement shall not be considered
a novation of account or new contract but that all existing rights, titles,
powers, and estates in favor of the Lenders constitute valid and existing
obligations in favor of the Lenders. Borrower confirms and agree that (a)
neither the execution of this Amendment nor any other Loan Document nor the
consummation of the transactions described herein and therein shall in any way
effect, impair or limit the covenants, liabilities, obligations and duties of
the Borrower under the Loan Documents and (b) the obligations evidenced and
secured by the Loan Documents continue in full force and effect.

SECTION 5. STERLING ACQUISITION POST-CLOSING COVENANTS.

         5.1      BORROWING BASE INCREASE FEE. On the Sterling Acquisition
Closing Date, the Borrower shall pay to the Agent, for the ratable benefit of
the Lenders, a Borrowing Base increase fee equal to one-quarter of one percent
(.25%) of the amount of the increase in the Borrowing Base from the amount in
effect prior to the effectiveness of this Amendment, which fee is due and
payable on the date hereof. Borrower further agrees that any failure on its part
to comply with and perform this covenant shall constitute an Event of Default
under the Credit Agreement.

         5.2      STERLING ACQUISITION DEEDS OF TRUST. On the Sterling
Acquisition Closing Date, the Borrower shall execute and deliver deeds of trust
covering the properties acquired in connection with the Sterling Acquisition to
secure the indebtedness, liabilities and obligations of Borrower with respect to
the Notes and the Credit Agreement in form and substance acceptable to the
Agent. Borrower further agrees that any failure on its part to comply with and
perform this covenant shall constitute an Event of Default under the Credit
Agreement.

         5.3      STERLING ACQUISITION PURCHASE AGREEMENT. Promptly after the
Sterling Acquisition Closing Date, the Borrower shall deliver true and correct
copies of the Sterling Acquisition Purchase Agreement and all material documents
executed by Borrower's wholly-owned subsidiary Range Production I, L.P. in
connection with the Sterling Acquisition. The Borrower further agrees that any
failure on its part to comply with and perform this covenant shall constitute an
Event of Default under the Credit Agreement.

                            [SIGNATURE PAGES FOLLOW]

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         IN WITNESS WHEREOF, the parties have caused this Seventh Amendment to
Amended and Restated Credit Agreement to be duly executed as of the date first
above written.

                                           BORROWER:

                                           RANGE RESOURCES CORPORATION
                                           a Delaware corporation

                                           By:    /s/ Roger S. Manny
                                              ----------------------------------
                                           Name:  Roger S. Manny
                                           Title: Senior Vice President

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                                           LENDERS:

                                           BANK ONE, NA, a national banking
                                           association (Main Office Chicago)
                                           as a Lender and Administrative Agent

                                           By:    /s/ Thomas E. Both
                                              ----------------------------------
                                           Name:  Thomas E. Both
                                           Title: Director, Capital Markets

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                                           BANK OF SCOTLAND

                                           By:    /s/ Joseph Fratus
                                              ----------------------------------
                                           Name:  JOSEPH FRATUS
                                           Title: FIRST VICE PRESIDENT

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                                           JPMORGAN CHASE BANK

                                           By:    /s/ Robert C. Mertensotto
                                              ----------------------------------
                                           Name:  ROBERT C. MERTENSOTTO
                                           Title: MANAGING DIRECTOR

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                                           COMPASS BANK

                                           By:    /s/ Murray E. Brasseux
                                              ----------------------------------
                                           Name:  Murray E. Brasseux
                                           Title: Executive Vice President

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                                           CREDIT LYONNAIS NEW YORK BRANCH

                                           By:    /s/ Olivier Audemard
                                              ----------------------------------
                                           Name:  Olivier Audemard
                                           Title: Senior Vice President

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                                          FLEET NATIONAL BANK

                                          By: /s/ Jeffrey H. Rathkamp
                                              -----------------------
                                          Name: JEFFREY H. RATHKAMP
                                          Title: DIRECTOR

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                                          FORTIS CAPITAL CORP.

                                          By: /s/ Christopher S. Parada
                                              -------------------------
                                          Name:  Christopher S. Parada
                                          Title: Vice President

                                          By: /s/ Darrell W. Holley
                                              ---------------------
                                          Name:  Darrell W. Holley
                                          Title: Managing Director

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                                          NATEXIS BANQUES POPULAIRES

                                          By: /s/ Donovan C. Broussard
                                              ------------------------
                                              Donovan C. Broussard
                                              Vice President & Group Manager

                                          By: /s/ Philippe A. Robin
                                              ---------------------
                                              Philippe A. Robin
                                              Senior Vice President

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                                          COMERICA BANK
                                          (successor by merger with
                                          Comerica Bank-Texas)

                                          By: /s/ Michele L. Jones
                                              ---------------------
                                          Name:  Michele L. Jones
                                          Title: Vice President-Texas Division

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                                          HIBERNIA NATIONAL BANK

                                          By: /s/ Daria Mahoney
                                              -----------------
                                          Name:  Daria Mahoney
                                          Title: Vice President

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                                          SOUTHWEST BANK OF TEXAS, N.A.

                                          By: /s/ W. Bryan Chapman
                                              ------------------------
                                          Name:  W. Bryan Chapman,
                                          Title: Senior Vice President,
                                                 Energy Lending

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                            CONSENT AND REAFFIRMATION

         The undersigned (each a "Guarantor") hereby (i) acknowledges receipt of
a copy of the foregoing Seventh Amendment to Amended and Restated Credit
Agreement (the "Seventh Amendment"); (ii) consents to Borrower's execution and
delivery thereof; (iii) agrees to be bound thereby; (iv) affirms that nothing
contained therein shall modify in any respect whatsoever its guaranty of the
obligations of the Borrower to Lenders pursuant to the terms of its Guaranty in
favor of Agent and the Lenders (the "Guaranty") and (v) reaffirms that the
Guaranty is and shall continue to remain in full force and effect. Although
Guarantor has been informed of the matters set forth herein and has acknowledged
and agreed to same, Guarantor understands that the Lenders have no obligation to
inform Guarantor of such matters in the future or to seek Guarantor's
acknowledgment or agreement to future amendments or waivers, and nothing herein
shall create such duty.

         IN WITNESS WHEREOF, the undersigned has executed this Consent and
Reaffirmation on and as of the date of the Seventh Amendment.

                                          GUARANTORS:

                                          RANGE ENERGY I, INC.
                                          a Delaware corporation

                                          By: /s/ Roger S. Manny
                                              ------------------
                                          Name: Roger S. Manny
                                          Title: Senior Vice President

                                          RANGE HOLDCO, INC.
                                          a Delaware corporation

                                          By: /s/ Roger S. Manny
                                              ------------------
                                          Name: Roger S. Manny
                                          Title: Senior Vice President

                                          RANGE PRODUCTION COMPANY
                                          a Delaware corporation

                                          By: /s/ Roger S. Manny
                                              ------------------
                                          Name: Roger S. Manny
                                          Title: Senior Vice President

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                                          RANGE ENERGY VENTURES
                                          CORPORATION, a Delaware corporation

                                          By: /s/ Roger S. Manny
                                              ------------------
                                          Name: Roger S. Manny
                                          Title: Senior Vice President

                                          GULFSTAR ENERGY, INC.
                                          a Delaware corporation

                                          By: /s/ Roger S. Manny
                                              ------------------
                                          Name: Roger S. Manny
                                          Title: Senior Vice President

                                          RANGE ENERGY FINANCE CORPORATION
                                          a Delaware corporation

                                          By: /s/ Roger S. Manny
                                              ------------------
                                          Name: Roger S. Manny
                                          Title: Senior Vice President

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                                    EXHIBIT B
                                 REVOLVING NOTE

$[ ]                              Dallas, Texas               December [ ], 2003

         FOR VALUE RECEIVED, the undersigned RANGE RESOURCES CORPORATION, a
Delaware corporation ("Borrower") hereby, unconditionally promises to pay to the
order of [ ] (the "Lender") at the offices of BANK ONE, NA (the "Agent") in
Dallas County, Texas, the principal sum of [        ], or so much thereof as may
be advanced and outstanding at any time or from time to time pursuant to the
Amended and Restated Credit Agreement (as hereinafter defined) in lawful money
of the United States of America together with interest from the date hereof
until paid at the rates specified in the Amended and Restated Credit. All
payments of principal and interest due hereunder are payable at the offices of
Agent at Bank One, NA, Mail Code IL-0634, 1 Bank One Plaza, Chicago, Illinois
60670-0634, Facsimile No.: (312) 732-4840, Attention: Jim Moore, with a copy to
1717 Main Street, 4th Floor, Bank One Center, Dallas, Texas 75201, attention:
Energy Department, or at such other address as Lender shall designate in writing
to Borrower.

         The principal and all accrued interest on this Note shall be due and
payable in accordance with the terms and provisions of the Credit Agreement.

         This Note is executed pursuant to that certain Amended and Restated
Credit Agreement (the "Credit Agreement") dated May 2, 2002 by and among
Borrower, the Agents and Lender, and is one of the Notes referred to therein.
Reference is made to the Credit Agreement and the Loan Documents (as that term
is defined in the Credit Agreement) for a statement of prepayment rights and
obligations of Borrower, for a statement of the terms and conditions under which
the due date of this Note may be accelerated and for statements regarding other
matters affecting this Note (including without limitation the obligations of the
holder hereof to advance funds hereunder, principal and interest payment due
dates, voluntary and mandatory prepayments, exercise of rights and remedies,
payment of attorneys' fees, court costs and other costs of collection and
certain waivers by Borrower and others now or hereafter obligated for payment of
any sums due hereunder). Upon the occurrence of an Event of Default (as that
term is defined in the Credit Agreement and Loan Documents) the Agent may
declare forthwith to be entirely and immediately due and payable the principal
balance hereof and the interest accrued hereon, and the Lender shall have all
rights and remedies of the Lender under the Credit Agreement and Loan Documents.
This Note may be prepaid in accordance with the terms and provisions of the
Credit Agreement.

         Regardless of any provision contained in this Note, the holder hereof
shall never be entitled to receive, collect or apply, as interest on this Note,
any amount in excess of the Maximum Rate (as such term is defined in the Credit
Agreement), and, if the holder hereof ever receives, collects, or applies as
interest, any such amount which would be excessive interest, it shall be deemed
a partial prepayment of principal and treated hereunder as such; and, if the
indebtedness evidenced hereby is paid in full, any remaining excess shall
forthwith be paid to Borrower. In determining whether or not the interest paid
or payable, under any specific contingency, exceeds the Maximum Rate, Borrower
and the holder hereof shall, to the maximum

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extent permitted under applicable law (i) characterize any non-principal payment
as an expense, fee or premium rather than as interest, (ii) exclude voluntary
prepayments and the effects thereof, and (iii) spread the total amount of
interest throughout the entire contemplated term of the obligations evidenced by
this Note and/or referred to in the Credit Agreement so that the interest rate
is uniform throughout the entire term of this Note; provided that, if this Note
is paid and performed in full prior to the end of the full contemplated term
thereof; and if the interest received for the actual period of existence thereof
exceeds the Maximum Rate, the holder hereof shall refund to Borrower the amount
of such excess or credit the amount of such excess against the indebtedness
evidenced hereby, and, in such event, the holder hereof shall not be subject to
any penalties provided by any laws for contracting for, charging, taking,
reserving or receiving interest in excess of the Maximum Rate.

         If any payment of principal or interest on this Note shall become due
on a day other than a Business Day (as such term is defined in the Credit
Agreement), such payment shall be made on the next succeeding Business Day and
such extension of time shall in such case be included in computing interest in
connection with such payment.

         If this Note is placed in the hands of an attorney for collection, or
if it is collected through any legal proceeding at law or in equity or in
bankruptcy, receivership or other court proceedings, Borrower agrees to pay all
costs of collection, including, but not limited to, court costs and reasonable
attorneys' fees.

         Borrower and each surety, endorser, guarantor and other party ever
liable for payment of any sums of money payable on this Note, jointly and
severally waive presentment and demand for payment, notice of intention to
accelerate the maturity, protest, notice of protest and nonpayment, as to this
Note and as to each and all installments hereof, and agree that their liability
under this Note shall not be affected by any renewal or extension in the time of
payment hereof, or in any indulgences, or by any release or change in any
security for the payment of this Note, and hereby consent to any and all
renewals, extensions, indulgences, releases or changes.

         This Note shall be governed by and construed in accordance with the
applicable laws of the United States of America and the laws of the State of
Texas.

         THIS INSTRUMENT SECURES A LINE OF CREDIT USED PRIMARILY FOR BUSINESS,
COMMERCIAL OR AGRICULTURAL PURPOSES.

         THIS WRITTEN NOTE, THE CREDIT AGREEMENT AND THE OTHER LOAN DOCUMENTS
REPRESENT THE FINAL AGREEMENTS BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED
BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE
PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

         This Note amends, modifies, and restates, but does not extinguish, the
indebtedness evidenced by that certain Revolving Note of Borrower dated [     ]
payable to the order of Bank in the original principal amount of $[      ],
executed by Borrower and payable to the order of Bank.

Seventh Amendment to Amended and Restated Credit Agreement - Signature Page
DALLAS 1315126
<PAGE>

EXECUTED as of the date and year first above written.

                                          BORROWER:

                                          RANGE RESOURCES CORPORATION
                                          a Delaware corporation

                                          By: /s/ Roger S. Manny
                                              ------------------
                                          Name: Roger S. Manny
                                          Title: Senior Vice President

Sixth Amendment to Amended and Restated Credit Agreement - Signature Page
DALLAS 1315126
<PAGE>

                                   SCHEDULE 1

<TABLE>
<CAPTION>
        LENDER                                     COMMITMENT
        ------                                     -----------
<S>                                                <C>
BANK ONE, NA                                       $26,000,000
BANK OF SCOTLAND                                   $26,000,000
CREDIT LYONNAIS NEW YORK BRANCH                    $26,000,000
FLEET NATIONAL BANK                                $26,000,000
FORTIS CAPITAL CORP.                               $26,000,000
JPMORGAN CHASE                                     $26,000,000
COMPASS BANK                                       $18,000,000
COMERICA BANK                                      $17,500,000
NATEXIS BANQUES POPULAIRES                         $13,500,000
SOUTHWEST BANK OF TEXAS, N.A.                      $10,000,000
HIBERNIA NATIONAL BANK                             $10,000,000
</TABLE>

Seventh Amendment to Amended and Restated Credit Agreement - Signature Page
DALLAS 1315126<PAGE>

Exhibit 10.4

                       RAW MATERIAL REQUIREMENTS AGREEMENT

         THIS AGREEMENT made as of June 1st, 2003, between C-E Minerals Inc., a
corporation organized and existing under the laws of the state of Delaware and
having an office at 901 East Eighth Avenue, King of Prussia, Pennsylvania 19406
(hereinafter "C-E"), and CARBO Ceramics Inc., a corporation organized and
existing under the laws of the state of Delaware and having an office at 6565
MacArthur Blvd., Suite 1050, Irving, Texas 75039-2461 (hereinafter "CARBO").

                              W I T N E S S E T H:

         CARBO desires to purchase a supply of kaolin, a naturally occurring
mineral more particularly described (and meeting the specifications set forth)
in Appendix A hereto (the "Product", also sometimes called "clay" or "ore"), for
use in the manufacture of ceramic proppants.

         C-E is able and desires to supply CARBO with such Product on the terms
and conditions hereinafter set forth.

         NOW, THEREFORE, in consideration of the premises, the parties agree as
follows:

1.       TERM

         The term of this Agreement shall be seven (7) years commencing January
1, 2004 and ending December 31, 2010.

2.       QUANTITY

         A.       During the term of this Agreement, C-E shall make available
                  for sale to CARBO each year and CARBO shall have the right to
                  purchase from C-E each year up to 200,000 net tons of the
                  Product.

         B.       In each year during the term of this Agreement, subject to
                  Paragraph 2.A hereof, CARBO shall be obligated to purchase
                  from C-E, as a minimum, seventy percent (70%) of its actual
                  annual requirements of the Product during such year for its
                  operations in Eufaula, Alabama.

         C.       CARBO may specify that up to 25% of the Product provided
                  pursuant to this Agreement come from the Andersonville local
                  low Alumina ores (approximately * Alumina). For the quantity
                  of ores provided from Andersonville from time to time C-E
                  shall provide sufficient quantities of ores from other
                  locations to enable CARBO to blend the ores to achieve the
                  specifications set out on Appendix A. Notwithstanding the
                  aforementioned ore source specifications, the ores delivered
                  to

----------
* Confidential Information in this Exhibit 10.4 has been omitted and filed
separately with the Securities and Exchange Commission.

<PAGE>

                  the CARBO Eufaula Plant will meet the product specifications
                  (See Appendix A) on average for each 1,000 Tons delivered.

3.       DELIVERY

         A.       CARBO shall advise C-E on or before October 1 of each year,
                  beginning October 1, 2003, of the tonnage of the Product it
                  projects to purchase during the next calendar year for use at
                  its Eufaula Plant. Such projections shall be estimates only
                  and CARBO shall not be committed to accept deliveries of such
                  amounts. CARBO shall use reasonable business efforts to advise
                  C-E promptly in the event of any change in its annual purchase
                  projections for any year.

         B.       C-E and CARBO shall communicate regularly, and C-E shall use
                  its best efforts to ensure the availability of Product for
                  sale hereunder on an "as needed" basis. CARBO shall use its
                  best efforts (to extent feasible) to space evenly its actual
                  purchase orders for Product, and C-E shall (subject to
                  paragraph 2.A hereof) be obligated to fill such orders. Each
                  such purchase order shall be subject to all of the terms and
                  conditions of this Agreement.

         C.       Delivery of the Product as supplied from Eufaula local C-E
                  Mines shall be F.O.B. open truck, C-E's mine stockpile in
                  Barbour and/or Henry Counties, Alabama ("C-E's Mines"), or
                  other deposits mutually agreed upon. CARBO shall be
                  responsible for the scheduling of and payment for transport of
                  Product from C-E's Local Mines (or such other deposits
                  mutually agreed upon). Product as supplied from C-E
                  Andersonville deposits shall be delivered, at C-E's expense,
                  by C-E arranged trucks to CARBO's Eufaula Plant ore storage
                  location.

         D.       Risk of loss and title for local C-E clays pass to CARBO upon
                  delivery to CARBO's designated carrier at C-E's mine, or other
                  deposits mutually agreed upon. Risk of loss and title for C-E
                  Andersonville clays pass to CARBO upon delivery and unload at
                  CARBO's Eufaula Plant ore storage.

         E.       CE agrees to continue the practice of stockpiling a "wet
                  weather" reserve for CARBO under the terms and at the location
                  described in Appendix C.

4.       PRICE

         A.       The price for the Product purchased from C-E shall be: $ * per
                  net ton delivered to CARBO from C-E Andersonville deposits and
                  $ * per net ton F.O.B. C-E local Eufaula mines or other local
                  deposits as agreed upon.

----------
* Confidential Information in this Exhibit 10.4 has been omitted and filed
separately with the Securities and Exchange Commission.

                                      -2-
<PAGE>

         B.       The prices shall be adjusted on January 1 of each year,
                  beginning January 1, 2005, using the previous September's
                  Producer Price Index ("PPI") for kaolin and ball clay,
                  published by the US Department of Labor, Bureau of Labor
                  Statistics. (An example of the calculation intended to be
                  performed by the parties is set forth in Appendix B hereto.)
                  If, during the term of this Agreement, the PPI should increase
                  or decrease by an amount in excess of 8% in any calendar year,
                  the parties shall meet to negotiate an equitable price
                  adjustment for each subsequent year during such term. In the
                  event the parties cannot agree on a price adjustment within
                  thirty (30) days after the applicable PPI change, either party
                  may terminate this Agreement by written notice to the other.

                  If the PPI is discontinued and substantially the same basic
                  data is used to compile a similar index, such similar index
                  shall be used. If the PPI is discontinued and no such similar
                  index shall be compiled, the parties shall negotiate in good
                  faith in order to agree upon another substitute index. If such
                  negotiations do not result in timely agreement as to a
                  substitute index either party may terminate this Agreement by
                  written notice to the other.

5.       NON-COMPETE

         Without intending to limit the legal rights of either party, CARBO and
         C-E agree as follows: that CARBO will not enter into direct competition
         with C-E in the manufacture of calcined clay for general sale to
         refractory or other related industry, and that C-E will not enter into
         competition with CARBO in the manufacture or sale of ceramic proppants.
         This agreement will endure for 3 years after the expiration of this
         contract.

6.       PAYMENT

         Payment for conforming Product sold and delivered hereunder shall be
         net thirty (30) days from date of invoice. Invoices shall be sent on a
         monthly basis. Invoices shall include a copy of the weight-ticket
         covering the Product being invoiced.

7.       ASCERTAINMENT OF WEIGHT

         The weight of the Product delivered shall be determined by weighing on
         state-certified scales acceptable to both parties. C-E and CARBO shall
         maintain all required certification documentation on file at all times
         at the site of such scales.

8.       WARRANTY

         C-E warrants that the Product when delivered will conform to the
         specifications contained in Appendix A hereto for every 1,000 tons of
         Product so delivered. C-E warrants that the Product delivered hereunder
         shall be free of contaminants and other foreign substances rendering
         the Product unsuitable for the economic use of Owner.

                                      -3-
<PAGE>

9.       INDEMNIFICATION

         To the fullest extent permitted by law, C-E shall indemnify and hold
         harmless CARBO, and agents and employees of CARBO from and against
         claims, damages, losses and expenses, including but not limited to
         attorneys' fees, arising out of or resulting from performance of this
         Agreement, provided that such claim, damage, loss or expense is
         attributable to bodily injury, sickness, disease or death, or to injury
         to or destruction of tangible property (other than the Product itself)
         including loss of use resulting therefrom, but only to the extent
         caused in whole or in part by negligent acts or omissions or breach of
         this Agreement by C-E or anyone directly or indirectly employed by C-E
         or anyone for whose acts C-E may be liable, regardless of whether or
         not such claim, damage, loss or expense is caused in part by the
         negligence of a party indemnified hereunder.

10.      INSURANCE

         C-E shall purchase from and maintain in a company or companies lawfully
         authorized to do business in the State of Alabama such insurance as
         will protect C-E and CARBO from which may arise out of or result from
         C-E's operations under this Agreement and for which C-E may be legally
         liable, whether such operations be by C-E or by a subcontractor or by
         anyone directly or indirectly employed by any of them, or by anyone for
         whose acts any of them may be liable.

         C-E shall maintain worker's compensation in at least the minimum amount
         stipulated under the Alabama's worker's compensation statutes,
         including Employers Liability. Such insurance policy shall include a
         waiver of subrogation of the insurers thereunder against CARBO and of
         any right of the insurers to any set-off or counterclaim or any other
         deduction, whether by attachment of otherwise, in respect of any
         liability of any person or entity insured under any such policy.

11.      NOTICE

         All notices under this Contract required or permitted to be given by
         CARBO to C-E and all payments to be made by CARBO to C-E hereunder
         shall be delivered personally to C-E or sent to C-E at the address set
         out at the beginning of this Agreement, or at such other address as C-E
         may hereafter furnish in the manner provided herein to CARBO.

         All notices herein required or permitted to be given by C-E to CARBO
         shall be sent by registered or certified United States mail, return
         receipt requested, addressed to CARBO at CARBO Ceramics Inc., Attn.
         Paul G. Vitek, 6565 MacArthur Boulevard, Suite 1050, Irving, TX 75039,
         or at such other address as CARBO may hereafter furnish in the manner
         provided herein to C-E.

                                      -4-
<PAGE>

12.      FORCE MAJEURE

         A.       The term "Force Majeure" as used herein shall mean acts of
                  God, natural calamities, acts of the public enemy, blockades,
                  insurrections, strikes, slowdowns or differences with workmen,
                  riots, wars, disorders, civil disturbances, fires, explosions,
                  storms, floods, landslides, washouts, labor or material
                  shortages, boycotts, breakdowns or damage to plants, equipment
                  or facilities, interruptions to transport, embargoes, acts of
                  military authorities, acts of local or federal governmental
                  agencies or regulatory bodies, court actions, arrests and
                  constraints and, without limitation by enumeration, any other
                  cause or causes not reasonably within the control and without
                  the fault or negligence of the party affected which wholly or
                  partly prevents the mining, processing, loading or
                  transportation of Product by C-E or the receiving,
                  transporting, accepting or using of Product by CARBO.

         B.       If because of Force Majeure, either party hereto is unable to
                  carry out its obligations under this Agreement and if such
                  party shall promptly give to the other notice by telex or
                  telephone of such Force Majeure, including a complete
                  description thereof, then the obligation of the party giving
                  such notice shall be suspended to the extent made necessary by
                  Force Majeure and during its continuance; provided, however,
                  that the party giving such notice shall use its best efforts
                  to eliminate such Force Majeure insofar as possible with a
                  minimum of delay. No event of Force Majeure shall relieve
                  CARBO of its obligation to make payments due for Product
                  delivered by C-E under this Agreement. Deficiencies in
                  deliveries or acceptance of Product caused by an event of
                  Force Majeure shall only be made up by mutual consent.

13.      ENTIRE AGREEMENT

         This written instrument contains the entire agreement between the
         parties hereto concerning the subject matter hereof, and there are no
         other understandings or agreements between said parties or either of
         them in respect hereto. No change, addition to or waiver of the terms
         and provision hereof shall be binding upon either party unless approved
         in writing by an authorized representative of such party, and no
         modifications shall be effected by the acknowledgment or acceptance of
         forms containing other or different terms and conditions. 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
         a single instrument.

14.      ASSIGNMENT

         This Agreement shall be binding on the legal successors of the parties
         hereto, but shall not otherwise be assignable by either party without
         the written consent of the other.

                                      -5-
<PAGE>

15.      APPLICABLE LAW

         This Agreement and the language used herein shall be construed and
         enforced in accordance with the laws of the State of Alabama.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the day and year first above written.

                                              C-E MINERALS INC.

                                              By     /s/ Michael K. Pierce
                                                     ---------------------------

                                              Name:  Michael K. Pierce

                                              Title: Vice President of Sales

                                              CARBO CERAMICS INC.

                                              By     /s/ Mark L. Edmunds
                                                     ---------------------------

                                              Name:  Mark Edmunds

                                              Title: Vice President, Operations

                                      -6-
<PAGE>

                                   APPENDIX A

                            SPECIFICATIONS FOR KAOLIN

                  QUALITY SPECIFICATIONS (on a calcined basis)

                        (Average Over 1,000 T Delivered)

Al(2)O(3) Content

            Weekly Average                              *%

            Minimum Individual Sample                   *%

            Maximum Individual Sample                   *%

Fe(2)O(3) Content

            Maximum                                     *%

            Typical                                     *%

--------
* Confidential Information in this Exhibit 10.4 has been omitted and filed
separately with the Securities and Exchange Commission.

                                      A-2
<PAGE>

                                   APPENDIX B

1. Annual Adjustment of Base Price Per Ton (example):

         Base Price Per Ton                                            $ *

         Average Monthly PPI for Kaolin and Ball Clay for 2003          133.4

         Average Monthly PPI for Kaolin and Ball Clay for 2004          130.3

         Percentage Change                                              (2.32%)

         Revised Base Price Per Ton                                    $ *

--------
* Confidential Information in this Exhibit 10.4 has been omitted and filed
separately with the Securities and Exchange Commission.

                                      A-2
<PAGE>

                                   APPENDIX C

Replacing the side agreement between Robin Dozier of CE Minerals and Tom
Palamara of CARBO Ceramics Inc.:

OBJECTIVE

To provide ore availability to CARBO Ceramics Inc. during periods of wet weather
(which can prevent hauling from the mine sites). CE Minerals will store a
mutually agreed upon tonnage of appropriate alumina content raw materials for
CARBO Ceramics Inc. at the former A.P. Green plant site.

PRICE

CE Minerals will invoice CARBO Ceramics Inc. for half of the contract price of
the ores when stockpiled, the remaining half of the contract price is to be
invoice upon delivery; plus shipping and handling cost incurred by CE Minerals
for the following:

         1.       Loading of ores at the various stockpile locations. ($ * per
                  ton)

         2.       Trucking of ores from the various stockpile locations to the
                  former A.P. Green plant site. Rates are as follows:

<TABLE>
<CAPTION>
DISTANCE (MILES)                                   RATE ($) PER TON
<S>                                                <C>
        1                                                  *
        2                                                  *
        3                                                  *
        4                                                  *
        5                                                  *
        6                                                  *
        7                                                  *
        8                                                  *
        9                                                  *
       10                                                  *
</TABLE>

         Mileage will be rounded to the nearest mile and rates interpolated
where required.

         3.       Weighing of the trucks on certified scales at the former A.P.
                  Green plant site and pushing up the piles. ($* per ton)

--------
* Confidential Information in this Exhibit 10.4 has been omitted and filed
separately with the Securities and Exchange Commission.

                                      A-3

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