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                                                                     EXHIBIT 4.2


                                 AMENDMENT NO. 1
                                       TO
                           FIRST AMENDED AND RESTATED
                        AGREEMENT OF LIMITED PARTNERSHIP
                                       OF
                         NATURAL RESOURCE PARTNERS L.P.


         This Amendment No. 1 (this "Amendment No. 1") to the First Amended and
Restated Agreement of Limited Partnership of Natural Resource Partners L.P. (the
"Partnership") is entered into effective as of December 8, 2003, by NRP (GP) LP,
a Delaware limited partnership (the "General Partner"), as general partner of
the Partnership. Capitalized terms used but not defined herein are used as
defined in the Partnership Agreement.

         WHEREAS, the General Partner, the Organizational Limited Partner and
the Limited Partners of the Partnership entered into that certain First Amended
and Restated Agreement of Limited Partnership of the Partnership dated as of
October 17, 2002 (the "Partnership Agreement");

         WHEREAS, Section 13.1(d)(i) of the Partnership Agreement provides that
the General Partner may amend any provision of the Partnership Agreement without
the approval of any Partner or Assignee to reflect a change that, in the
discretion of the General Partner, does not adversely affect the Limited
Partners (including any particular class of Partnership Interests as compared to
other classes of Partnership Interests) in any material respect; and

         WHEREAS, acting pursuant to the power and authority granted to the
General Partner under Section 13.1(d)(i) of the Partnership Agreement, the
General Partner has determined that the following amendment to the Partnership
Agreement does not adversely affect the Limited Partners (including any
particular class of Partnership Interests as compared to other classes of
Partnership Interests) in any material respect.

         NOW THEREFORE, the General Partner does hereby amend the Partnership
Agreement as follows:

         Section 1.        Amendment.

                  (a)      Section 5.7(b) is hereby amended and restated as
                           follows:

                           (b) During the Subordination Period, the Partnership
                  may also issue an unlimited number of Common Units and other
                  Parity Units without the prior approval of the Unitholders, if
                  such issuance occurs (i) in connection with an Acquisition or
                  a Capital Improvement or (ii) within 365 days of, and the net
                  proceeds from such issuance are used to repay debt incurred in
                  connection with, an Acquisition or a Capital Improvement, in
                  each case where such Acquisition or Capital Improvement
                  involves assets that, if acquired (or in the case of a Capital

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                  Improvement, put into commercial service) by the Partnership
                  as of the date that is one year prior to the first day of the
                  Quarter in which such Acquisition was consummated or such
                  Capital Improvement was put into commercial service ("One Year
                  Test Period"), would have resulted, on a pro forma or
                  estimated pro forma basis (as described below), in an increase
                  in:

                                    (A) the amount of Adjusted Operating Surplus
                           generated by the Partnership on a per-Unit basis (for
                           all Outstanding Units) with respect to the One Year
                           Test Period (on a pro forma or estimated pro forma
                           basis as described below) as compared to

                                    (B) the actual amount of Adjusted Operating
                           Surplus generated by the Partnership on a per-Unit
                           basis (for all Outstanding Units) with respect to the
                           One Year Test Period as adjusted as provided below.

                  The General Partner's good faith determination that such an
                  increase would have resulted shall be conclusive. The amount
                  in clause (A) shall be determined on a pro forma or estimated
                  pro forma basis assuming that (1) all of the Parity Units to
                  be issued in connection with or within 365 days of such
                  Acquisition or Capital Improvement had been issued and
                  outstanding as of the commencement of such One Year Test
                  Period, (2) all indebtedness for borrowed money to be incurred
                  or assumed in connection with such Acquisition or Capital
                  Improvement (other than any such indebtedness that is to be
                  repaid with the proceeds of such issuance of Parity Units) had
                  been incurred or assumed, in each case as of the commencement
                  of the One Year Test Period, (3) the personnel expenses that
                  would have been incurred by the Partnership in the operation
                  of the acquired assets are the personnel expenses for
                  employees to be retained by the Partnership in the operation
                  of the acquired assets, and (4) the personnel expenses that
                  would have been incurred by the Partnership in the operation
                  of the constructed assets and the non-personnel costs and
                  expenses that would have been incurred by the Partnership in
                  the operation of the acquired or constructed assets are
                  computed on the same basis as those incurred by the
                  Partnership in the operation of the Partnership's business at
                  similarly situated Partnership facilities or, if there are no
                  such similarly situated facilities, as estimated by the
                  General Partner in good faith using such assumptions as in its
                  sole discretion it believes are reasonable. If (1) the
                  Partnership makes a Capital Improvement or (2) the Partnership
                  makes an Acquisition for which no financial statements are
                  required to be furnished pursuant to Regulation S-X under the
                  Securities Exchange Act of 1934, then the amount of Adjusted
                  Operating Surplus in clause (A) attributable to such
                  Acquisition or Capital Improvement shall be estimated by the
                  General Partner in good faith using such assumptions as in its
                  sole discretion it believes are reasonable. In determining
                  Adjusted Operating Surplus attributable to an Acquisition or a
                  Capital Improvement, there shall be excluded from the amount
                  in


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                  clause (B) above (i) any Operating Surplus attributable to
                  such Acquisition or Capital Improvement (regardless of whether
                  such Operating Surplus is positive or negative), and (ii) for
                  the purpose of calculating the number of outstanding Units,
                  any Units issued to finance the Acquisition or Capital
                  Improvement. The number of Units, excluding any Common Units
                  or other Parity Units to be issued in connection with or
                  within 365 days of such Acquisition or Capital Improvement,
                  deemed to be Outstanding for the purpose of calculating the
                  amounts in clause (A) and clause (B) shall be the weighted
                  average number of Units Outstanding during the One Year Test
                  Period. For the purposes of this Section 5.7(b), the term
                  "debt" shall be deemed to include the indebtedness used to
                  extend, refinance, renew, replace or defease debt originally
                  incurred in connection with an Acquisition or Capital
                  Improvement; provided, that, the amount of such indebtedness
                  does not exceed the principal sum of, plus accrued interest
                  on, the indebtedness so extended, refinanced, renewed,
                  replaced or defeased.

                  (b)      Section 5.7 is amended to add a new subsection (g)
                           thereto as follows:

                           (g) During the Subordination Period, the Partnership
                  may also issue an unlimited number of Common Units and other
                  Parity Units without the prior approval of the Unitholders, if
                  the net proceeds of such issuance are used to redeem an equal
                  number of Common Units at a price per unit equal to the net
                  proceeds per unit, before expenses, that the Partnership
                  receives from such issuance.

         Section 2.        Ratification of Partnership  Agreement.  Except as
expressly  modified and amended herein,  all of the terms and conditions of the
Partnership Agreement shall remain in full force and effect.

         Section 3.        Governing  Law. This  Amendment  No. 1 will be
governed by and construed in accordance  with the laws of the State of Delaware.





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                                 SIGNATURE PAGE

                                 AMENDMENT NO. 1
                                       TO
           FIRST AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP
                        OF NATURAL RESOURCE PARTNERS L.P.
         IN WITNESS WHEREOF, the General Partner has executed this Amendment No.
1 as of the date first set forth above.


                                 GENERAL PARTNER:

                                 NRP (GP) LP

                                 BY:  GP NATURAL RESOURCE PARTNERS LLC,
                                      ITS GENERAL PARTNER

                                 By:  /s/ Wyatt L. Hogan
                                      --------------------------------------
                                      Name:  Wyatt Hogan
                                      Title: Vice President and General Counsel