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                                   EXHIBIT 2.5

Carbones de Guaduas. Ltda
CONVENIO DE CUENTAS EN PARTICIPACION
This Agreement of "Association" is executed by and between:

         VII.    ON THE ONE HAND, DR. ERASMO ALMANZA LATORRE, A CITIZEN OF
         COLOMBIA WITH CITIZENSHIP CARD NDEG 17.079, 078, WHO ACTS HEREIN IN
         HIS OWN NAME AND BEHALF, AND FOR THE PURPOSES OF THIS AGREEMENT HAS
         THE CAPACITY AS "ACTIVE PARTNER; AND

         VIII.   On the other hand,. CARBONES DE GUADUAS, LTDA., a limited
         liability company incorporated and existing under the Laws of
         Colombia. Hereinafter referred to as the Investing Partners, acting
         herein through its legal representative and authorized officer, Mr.
         Alain Loriquer;

WHEREAS:

1.       On April 23, 1998 an Agreement for a Coal Mining and Power
         Generation Project in Guaduas", was executed between the "Active
         Partner" on the one hand, and, on the other by Msres CARL SWAN,
         FRANK MAHAN, EUGENE CALLAWAY, ALAIN LORIQUER, JACK SCHRADER and
         ALVARO LOPEZ, each of them acted in common ("en comun y proindiviso
         por partes iguales"), by equal shares; such Agreement was extended
         by a document executed May 26, 1998.

2.       The above mentioned Agreement refers to the intention of the Parties
         to develop a Coal Mining Project in the municipality of Guaduas,
         "Departamento" of Cundinamarca, and any surrounding area, with the
         purpose of possibly further developing a project for power
         generation or any other project that may be financially and legally
         feasible under the laws and regulations of Colombia.

3.       Msres CARL SWAN, FRANK MAHAN, EUGENE CALLAWAY, ALAIN LORIQUER, JACK
         SCHRADER and ALVARO LOPEZ, have assigned to Magdalena Energia LLC a
         Limited Liability Company incorporated under the Laws of the State
         of Texas, and to Grupo Energia LLC a Limited Liability Company
         incorporated under the Laws of the State of Texas, all their rights
         and obligations under the aforementioned Agreements, and thus have
         created CARBONES DE GUADUAS, LTDA.

4.       The Active Partner acknowledges that he acts in his own name but on
         behalf of the Investing Partner.

5.       The Investing Partner maintains an interest in developing the
         coal-mining project for the further development of a power
         generation project and other possible purposes and ventures; and the
         Active Partner expects a compensation to be established in this
         instrument.

6.       In performance of the above mentioned agreement, on July 10, 1998,
         the Active Partner executed with ECOCARBON a "Contract for the
         Exploration and Exploitation of Coal - "Contrato de pequena
         exploracion y explotacion carbonifera"-, covering an area described
         in Clause 1.2 thereof within the municipality Guaduas.

7.       Also, in performance of the above mentioned agreement, the Active
         Partner submitted in his name but for the account of the Investing
         Partner, three (3) applications for the exploration and exploitation
         of areas - "solicitudes de exploracion y explotacion"-, for areas
         adjacent to the area covered by the Contract dated July 10, 1998.
         The applications are included within the following coordinates:

         a) parting from "Punto Arcifinio" 248 IC
         X: 106596000   Y: 946380     Area:    495 Has.   Vereda Tabaquera
         X: 106596000   Y: 946380     Area:    450 Has.   Vereda: Carbonera
                                                                  San Jose

         b) parting from- Punto Arcifinio 204-3A:
         X: 105304000   Y: 945990     Are26a:  420 Has.   Vereda: Chipauta -
                                                                  Carbonera


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         Active Partner has agreed to submit two additional applications in
         the neighboring areas, which have already been compensated for and
         the coordinates of which will be provided as soon as possible to
         Investing Partner.

8.       The Parties acknowledge the need to enter into this agreement of
         "association" while the feasibility studies for any of the above
         intended projects are concluded. Materialization of such projects is
         not an obligation; instead it will be the consequence of the
         conclusions of such feasibility studies.

9.       For the actions conducted to date by the Active Partner, he has been
         compensated by the individuals who have formed the Investing
         Partner, with the following amounts:

         -        Twenty million Pesos (Col $20.000.000), paid on
                  May 19, 1998, as a compensation for consulting services
                  provided through April 23, 1998.

         -        Four million Pesos ($4.257.443) paid on October 6, 1998, as
                  a compensation for the submittal of the second and third
                  "applications".

         -        The equivalent in Colombian Pesos to USD 4,500 paid as an
                  advance against the first installment of 50% of the Col Ps
                  110.000.000 as provided for in 2.1 of this agreement.

         BASED ON THE ABOVE CONSIDERATIONS, THE PARTIES AGREE AS FOLLOWS:

1.       OBLIGATIONS OF THE ACTIVE PARTNER:

         0.1      In relation to the existing Contract of July 10, 1998, the
                  Active Partner shall comply all the obligations therein
                  stated and shall ensure that it remains valid and
                  enforceable in all respects.

         0.2      In relation to the three (3) applications for exploration
                  and exploitation submitted, as well as any other application
                  as indicated above, also the Active Partner shall diligently
                  conduct all actions and processes necessary to make these
                  applications convertible into Contracts for Exploration and
                  Exploitation.

         0.3      To search for and obtain, for the benefit of the project all
                  technical, commercial and any other kind of information as
                  may be necessary or convenient for the successful
                  exploration and exploitation of coal reservoirs that may be
                  found in the areas and in other zones of the Colombian
                  territory.

         0.4      To advise the Investing Partner of any act or fact that may
                  affect the rights to explore and develop the coal mines in
                  the areas mentioned above.

         0.5      To refrain from conducting any assignment, alienation,
                  limitation to the property, mortgages or any other
                  encumbrance upon the rights derived from the contract and
                  the applications referred to above.

         0.6      To keep any and all technical, commercial or financial
                  information related to the rights under the contracts and
                  under this agreement strictly confidential

         0.7      To assign all and free of any and all encumbrance the rights
                  that he may have by virtue of this agreement, under the
                  Contract with ECOCARBON and under the applications above
                  mentioned, to the Investing Partner within the month
                  following receipt of the advise provided payments under
                  clause 2.1 and 2.2 are made and without prejudice to the
                  compensation agreed to in the form of a percentage of
                  profits described in clause 2.3 of this agreement.

         0.8      To grant the Investing Partner the right to participate,
                  under similar terms and conditions as obtained by the Active
                  Partner, in any Projects, whether commercial, industrial or
                  otherwise, on any lands, or interest in any lands, obtained
                  by the Active Partner, located within a 25 mile radius from
                  the perimeter of the area described in clause 1.2 of the
                  Contract entered into between the Active Partner and
                  ECOCARBON for the exploration and exploitation of coal,
                  dated July 10, 1998.

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2.       OBLIGATIONS OF THE INVESTING PARTNER:

         2.1      To pay the Active Partner the amount of One hundred ten
                  million Colombian Pesos (Col$110.000.000), in two
                  installments as follows:

                  a)       Fifty percent (50%) on the tenth (10th) working day
                           following execution of this agreement;

                  b)       Fifty percent (50%) on the twentieth (20th) working
                           day following execution of this agreement.

         2.1      To pay the Active Partner the total amount of Twenty five
                  thousand US Dollars (USD 25,000) divided into twelve (12)
                  equal monthly installments the first one becoming payable on
                  the same day as the amount described in 2.1(b) herein
                  above. Each one of these payments shall be made in Colombian
                  Pesos by converting the amount in dollars to pesos at the
                  Representative Market Exchange Rate as certified by the
                  Banking Superintendency for the day of payment.

         2.2      Once the corporate structure for the Mining and/or Power
                  Generation is established, where the Investing Partner has
                  an interest, then it will ensure that such company or
                  companies, resulting of this decision shall each agree with
                  the Active Partner on a share of profits in the amount of
                  two percent (2%) of the net distributable profits - after
                  taxes and reserves - as determined in the Balance Sheet and
                  other financial documents of each company.

         2.3      Payments contemplated in this clause as payable to Active
                  Partner, shall be made by Investing Partner according to
                  payment instructions received from Active Partner, provided
                  Beneficiary is clearly identified.

3.       APPLICABLE LAW AND ARBITRATION.

         The laws of the Republic of Colombia shall govern this agreement.

         Any dispute between the parties that may not be amicably resolved
         within the sixty (60) calendar days following the claim from one of
         the Parties, shall be submitted to the decision of an Arbitration
         tribunal that shall meet and decide according to the rules of the
         Center of Conciliation and Arbitration of Santafe de Bogota, D.C.,
         The tribunal shall be formed by 3 arbitrators appointed by the joint
         agreement of the Parties. In the absence of such agreement, the
         Parties delegate this decision upon the Center of Conciliation and
         Arbitration of Bogota. The Tribunal shall meet in Bogota and its
         ruling shall be in law.

4.       ADDRESSES OF THE PARTIES:

         For the purposes of information and advises between the Parties
         under this agreement, each one of them appoints the following agents
         and their address as follows:

         The Active Partner:                      The Investing Partner.
         ERASMO ALMANZA LATORRE                   ALAIN LORIQUER
         Diag.128C NDEG58-04                      Cra.11 NDEG115-08
         Tel.     271 7206                        Tel.     612 81 66
         Fax.     616 3774                        Fax.     612 81 66
         Santafe de Bogota D.C.                   Santafe de Bogota D.C.

5.       LANGUAGE:

         This agreement is executed simultaneously in both the English and
         the Spanish languages.

6.       EXPENSES AND TAXES.

         The Investing Partner shall pay the expenses for the authentication
         of signatures and recognition of this agreement as well as the stamp
         tax.

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IN WITNESS OF THE ABOVE THE PARTIES HAVE CAUSED THIS AGREEMENT TO BE EXECUTED IN
THE CITY OF SANTAFE DE BOGOTA D.C., THIS 6TH DAY OF APRIL 1999, BY:

The Active Partner                                 The Investing Partner:





/s/ERASMO ALMANZA                                   /s/ALAIN LORIQUER
                                           LEGAL REPRESENTATIVE
                                           CONRBONES DE GUADUAS, LTDA, Y
                                           POTOMAC ENERGY (BVI), LTD.






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