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                                                                   Exhibit 4.2.3
                                   DEBENTURE

     THESE SECURITIES AND THE SHARES ISSUABLE UPON CONVERSION HEREOF,
     HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
     AMENDED (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY
     STATE AND MAY NOT BE SOLD OR OFFERED FOR SALE IN THE ABSENCE OF
     AN EFFECTIVE REGISTRATION STATEMENT FOR THE SECURITIES OR AN
     OPINION OF COUNSEL OR OTHER EVIDENCE ACCEPTABLE TO THE
     CORPORATION THAT SUCH REGISTRATION IS NOT REQUIRED.

No.   CD-3                                                         US  $ 800,000
    -------                                                            ---------

                               RICH COAST, INC.

                  8% CONVERTIBLE DEBENTURE DUE JUNE 11, 2003


          THIS DEBENTURE is one of a duly authorized issue of $1,500,000 in
Debentures of RICH COAST, INC., a corporation duly organized and existing under
the laws of the State of Delaware (the "Company") designated as its 8%
Convertible Debentures Due June 11, 2003.

          FOR VALUE RECEIVED, the Company promises to pay to Dominion Capital
Fund Ltd., the registered holder hereof (the "Holder"), the principal sum of
$500,000 (US $) Dollars on June 11, 2003 (the "Maturity Date") and to pay
interest on the principal sum outstanding from time to time in arrears upon the
earlier of the Conversion Date, as defined below or June 11, 2003 at the rate of
8% per annum accruing from the date of initial issuance. Accrual of interest
shall commence on the first such business day to occur after the date hereof
until payment in full of the principal sum has been made or duly provided for.
Subject to the provisions of  paragraph 4 and paragraph 5 below, the principal
of, and interest on, this Debenture are payable at the option of the Holder, in
shares of Common Stock of the Company, $.001 par value ("Common Stock"), or in
such coin or currency of the United States of America as at the time of payment
is legal tender for payment of public and private debts, at the address last
appearing on the Debenture Register of the Company as designated in writing by
the Holder from time to time. The Company will pay the principal of and interest
upon this Debenture on the Maturity Date, less any amounts required by law to be
deducted, to the registered holder of this Debenture as of the tenth day prior
to the Maturity Date and addressed to such Holder at the last address appearing
on the Debenture Register. The forwarding of such check shall constitute a
payment of principal and interest hereunder and shall satisfy and discharge the
liability for principal and interest on this Debenture to the extent of the sum
represented by such check plus any amounts so deducted.

                                      -1-
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          This Debenture is subject to the following additional provisions:

          1.  The Debentures are issuable in denominations of Ten Thousand
Dollars (US$10,000) and integral multiples thereof. The Debentures are
exchangeable for an equal aggregate principal amount of Debentures of different
authorized denominations, as requested by the Holders surrendering the same. No
service charge will be made for such registration or transfer or exchange.

          2.  The Company shall be entitled to withhold from all payments of
principal of, and interest on, this Debenture any amounts required to be
withheld under the applicable provisions of the United States income tax laws or
other applicable laws at the time of such payments, and Holder shall execute and
deliver all required documentation in connection therewith.

          3.  This Debenture has been issued subject to investment
representations of the original holder  hereof and may be transferred or
exchanged only in compliance with the Securities Act of 1933, as amended (the
"Act"), and other applicable state and foreign securities laws. In the event of
any proposed transfer of this Debenture, the Company may require, prior to
issuance of a new Debenture in the name of such other person, that it receive
reasonable transfer documentation including opinions that the issuance of the
Debenture in such other name does not and will not cause a violation of the Act
or any applicable state or foreign securities laws. Prior to due presentment for
transfer of this Debenture, the Company and any agent of the Company may treat
the person in whose name this Debenture is duly registered on the Company's
Debenture Register as the owner hereof for the purpose of receiving payment as
herein provided and for all other purposes, whether or not this Debenture be
overdue, and neither the Company nor any such agent shall be affected by notice
to the contrary.

          4.  The Holder of this Debenture is entitled, at its option, to
convert at any time, the principal amount of this Debenture together with the
accrued interest thereon (and any other amounts due to the Holder hereunder),
into shares of Common Stock of the Company at a conversion price for each share
of Common Stock equal to the lesser of (i) the closing bid price of the shares
of Common Stock as reported by Bloomberg, LP on the date of issuance of the
Debentures (the "Fixed Conversion Price"), or (ii) seventy five (75%) of the
five day average closing bid price of the Common Stock, as reported by
Bloomberg, LP for the five trading days immediately preceding the applicable
Conversion Date (the "Conversion Price"). Conversion shall be effectuated by
surrendering the Debentures to be converted to the Company with the form of
conversion notice attached hereto as Exhibit A, executed by the Holder of the
Debenture evidencing such Holder's intention to convert this Debenture or a
specified portion (as above provided) hereof, and accompanied, if required by
the Company, by proper assignment hereof in blank. Interest accrued or accruing
from the date of issuance to the date of conversion shall, at the option of the
Holder, be paid in cash or Common Stock upon conversion at the Conversion Price.
No fractional shares or scrip representing fractions of shares will be issued on
conversion, but the number of shares issuable shall be rounded to the nearest
whole share. The date on which notice of conversion is given (the "Conversion
Date") shall be deemed to be the date on which the Holder has delivered this
Debenture, with the conversion notice duly executed, to the Company.  Facsimile
delivery of the conversion notice shall be accepted

                                      -2-
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          by the Company at telephone number (_____________; ATT: ___________).
Certificates representing Common Stock upon conversion will be delivered within
ten (10) days from the Conversion Date.

          (a)  In the event that the Company shall at any time after the date
          hereof (i) declare a dividend on the outstanding Common Stock payable
          in shares of its capital stock; (ii) subdivide the outstanding Common
          Stock; (iii) combine the outstanding Common Stock into a smaller
          number of shares; or (iv) issue any shares of its capital stock by
          reclassification of the Common Stock (including any such
          reclassification in connection with a consolidation or merger in which
          the Corporation is the continuing corporation), then, in each case,
          the Fixed Conversion Price in effect at the time of the record date
          for the determination of stockholders entitled to receive such
          dividend or distribution or of the effective date of such subdivision,
          combination, or reclassification shall be adjusted so that it shall
          equal the price determined by multiplying such Fixed Conversion Price
          by a fraction, the numerator of which shall be the number of shares of
          Common Stock outstanding immediately prior to such action, and the
          denominator of which shall be the number of shares of Common Stock
          outstanding after giving effect to such action.  Such adjustment shall
          be made successively whenever any event listed above shall occur and
          shall become effective at the close of business on such record date or
          at the close of business on the date immediately preceding such
          effective date, as applicable.

          5.   Except as otherwise provided in paragraph 9, in the event all or
any portion of this Debenture remains outstanding on the Maturity Date, the
unconverted portion of the Debenture will automatically be converted into shares
of Common Stock on such date in the manner set forth in paragraph  4 as if the
Maturity Date were the Conversion Date ("Mandatory Conversion").

          6.   Except in the case of Mandatory Conversion, in no event shall the
Holder be entitled to convert that amount of the Debenture in excess of that
amount upon conversion of which the sum of (1) the number of shares of Common
Stock beneficially owned by the Holder and its affiliates (other than shares of
Common Stock which may be deemed beneficially owned through the ownership of the
unconverted portion of the Debentures), and (2) the number of shares of Common
Stock issuable upon the conversion of the Debenture with respect to which the
determination of this proviso is being made, would result in beneficial
ownership by the Holder and its affiliates of more than 4.9% of the outstanding
shares of Common Stock of the Company. For purposes of the immediately preceding
sentence, beneficial ownership shall be determined in accordance with Section 13
(d) of the Securities Exchange Act of 1934, as amended, and Regulation 13 D-G
thereunder, except as otherwise provided in clause (1) of the immediately
preceding sentence.

          7.   In the event that the Common Stock is not delivered per the
written instructions of the Holder within five business days after the
Conversion Date in accordance with the terms hereof , then in such event the
Company shall pay to Holder one percent (1%) of the amount

                                      -3-
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          of the Debentures being converted per each day after the tenth (10th)
business day following the Conversion Date that the certificates for the shares
of Common Stock are not delivered in cash or shares of Common Stock, based upon
the Conversion Price at the option of the Holder.

          (a) The Company acknowledges that its failure to deliver the
          certificates for the shares of Common Stock within ten (10) days after
          the Conversion Date will cause the Holder to suffer damages in an
          amount that will be difficult to ascertain. Accordingly, the parties
          agree that it is appropriate to include in this Debenture a provision
          for liquidated damages. The parties acknowledge and agree that the
          liquidated damages provision set forth in this paragraph represents
          the parties' good faith effort to quantify such damages and, as such,
          agree that the form and amount of such liquidated damages are
          reasonable and do not constitute a penalty. The payment of liquidated
          damages shall not relieve the Company from its obligations to deliver
          the shares of Common Stock pursuant to the terms of this Debenture.

          (b) To the extent that the failure of the Company to issue the Common
          Stock pursuant to this paragraph 7 is due to the unavailability of
          authorized but unissued shares of Common Stock, the provisions of this
          paragraph 7 shall not apply but instead the provisions of paragraph 8
          shall apply.

          (c) The Company shall make the cash payment in immediately available
          funds or issue such shares of Common Stock incurred under this
          paragraph 7 within three (3) business days from the date of issuance
          of the applicable shares of Common Stock. Nothing herein shall limit a
          Holder's right to pursue actual damages or cancel the conversion for
          the Company's failure to issue and deliver the shares of Common Stock
          to the Holder within ten (10) business days after the Conversion Date.

          8.  The Company shall at all times reserve and have available the
number of shares of Common Stock issuable upon conversion of the Debentures then
outstanding. If, at any time Holder submits a Notice of Conversion and the
Company does not have a sufficient number of  authorized but unissued shares of
Common Stock available to effect, in full, a conversion of the Debentures (a
"Conversion Default," the date of such default being referred to herein as the
"Conversion Default Date"), the Company shall issue to the Holder all of the
shares of Common Stock which are available for issuance, and the Notice of
Conversion as to any Debentures requested to be converted but not converted (the
"Unconverted Debentures"), upon Holder's sole option, may be deemed null and
void. The Company shall provide notice of such Conversion Default ("Notice of
Conversion Default") to all existing Holders of outstanding Debentures, by
facsimile, within one (1) business day of such default (with the original
delivered by overnight or two day courier), and the Holder shall give notice to
the Company by facsimile within five business days of receipt of the original
Notice of Conversion Default (with the original delivered by overnight or two
day courier) of its election to either nullify or confirm the Notice of
Conversion.

          (a) The Company agrees to pay to all Holders of outstanding Debentures

                                      -4-
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          payments for a Conversion Default ("Conversion Default Payments") in
          the amount of (N/365) x (.24) x the original principal amount plus the
          accrued interest thereon of the outstanding and tendered but not
          converted Debentures held by each Holder where N = the number of days
          from the Conversion Default Date to the date (the "Authorization
          Date") that the Company authorizes a sufficient number of shares of
          Common Stock to effect conversion of all remaining Debentures. The
          Company shall send a notice ("Authorization Notice") to each Holder of
          outstanding Debentures that additional shares of Common Stock have
          been authorized, the Authorization Date and the amount of Holder's
          accrued Conversion Default Payments. The accrued Conversion Default
          Payments shall be paid in cash or shall be convertible into shares of
          Common Stock at the Conversion Price, at the Holder's option, payable
          as follows: (i) in the event Holder elects to take such payment in
          cash, cash payments shall be made to such Holder of outstanding
          Debentures by the fifth day of the calendar month following the
          Conversion Default Date and each month thereafter, or (ii) in the
          event Holder elects to take such payment in shares of Common Stock,
          the Holder may convert such payment amount into shares of Common Stock
          at the Conversion Price at anytime after the fifth day of the calendar
          month following the month in which the Authorization Notice was
          received, until the Mandatory Conversion Date.

          (b) The Company acknowledges that its failure to maintain a sufficient
          number of authorized but unissued shares of Common Stock to effect in
          full a conversion of the Debentures will cause the Holder to suffer
          damages in an amount that will be difficult to ascertain. Accordingly,
          the parties agree that it is appropriate to include in this Agreement
          a provision for liquidated damages. The parties acknowledge and agree
          that the liquidated damages provision set forth in this section
          represents the parties' good faith effort to quantify such damages
          and, as such, agree that the form and amount of such liquidated
          damages are reasonable and do not constitute a penalty.  The payment
          of liquidated damages shall not relieve the Company from its
          obligations to deliver the Common Stock pursuant to the terms of this
          Agreement.

          (c) Nothing herein shall limit the Holder's right to pursue actual
          damages or cancel the Notice of Conversion for the Company's failure
          to maintain a sufficient number of authorized shares of Common Stock.

          9.  In no event shall the Company be required to issue more than 20%
of the number of shares of Common Stock outstanding on the date hereof (the
"Maximum Number") upon the conversion of the Debentures unless the stockholders
of the Company approve the issuance of additional shares of Common Stock upon
the conversion of the Debentures or NASDAQ waives the requirements of Market
Place Rule 4460(i)(1)(D).  In the event that the Maximum Number of shares of
Common Stock have been issued upon the conversion of the Debentures, and (i)
NASDAQ has not waived the requirements of Market Place Rule 4460(i)(1)(D) or
(ii) the stockholders have not approved the issuance of additional shares of
Common Stock, then any Debentures that remain unconverted shall, at the election
of the Holder, be immediately due and payable at an amount equal

                                      -5-
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          to 133% percent of the sum of  (i) the principal amount of the
Debentures and (ii) an amount equal to any accrued and unpaid interest thereon,
within five (5) business days of the Holder's election.  The Company agrees to
take such corporate action as may be necessary to obtain the approval of the
stockholders, including the filing of a proxy statement with the Securities and
Exchange Commission within thirty (30) days of the date hereof, to issue
additional shares of Common Stock upon the conversion of the Debentures.  In the
event that the Company does not file the proxy statement within thirty (30) days
of the date hereof, the interest rate hereunder shall be increased by two (2%)
percent per month from the date hereof until the preliminary proxy statement is
filed.

          10.  No provision of this Debenture shall alter or impair the
obligation of the Company, which is absolute and unconditional, to pay the
principal of, and interest on, this Debenture at the time, place, and rate, and
in the coin or currency, herein proscribed provided, however, the Company may
prepay this Debenture in whole or in part without penalty as provided in
paragraph 11. This Debenture and all other Debentures now or hereafter issued of
similar terms are direct obligations of the Company.

          11.  The Company may redeem, in cash, the Debentures at any time, upon
giving a redemption notice, to the Holder at a redemption price equal to  133%
of the principal amount of, plus accrued interest on, the Debentures.   Except
as provided in this Section 11 the Debentures are not redeemable or prepayable.

          12.  Nothing contained in this Debenture shall be deemed to establish
or require the payment of interest to the Holder at a rate in excess of the
maximum rate permitted by governing law.  In the event that the rate of interest
required to be paid under the Debenture exceeds the maximum rate permitted by
governing law, the rate of interest required to be paid thereunder shall be
automatically reduced to the maximum rate permitted under the governing and any
amounts collected in excess of the permissible amount shall be deemed a payment
of principal.  To the extent that such excess amount exceeds the aggregate
principal amount of this Debenture, such excess shall be returned with
reasonable promptness by the holder to the Company.

          13.  If the Company merges or consolidates with another corporation or
sells or transfers all or substantially all of its assets to another person and
the holders of the Common Stock are entitled to receive stock, securities or
property in respect of or in exchange for Common Stock, then as a condition of
such merger, consolidation, sale or transfer, the Company and any such
successor, purchaser or transferee agree that the Debenture may thereafter be
converted on the terms and subject to the conditions set forth above into the
kind and amount of stock, securities or property receivable upon such merger,
consolidation, sale or transfer by a holder of the number of shares of Common
Stock into which this Debenture might have been converted immediately before
such merger, consolidation, sale or transfer, subject to adjustments which shall
be as nearly equivalent as may be practicable. In the event of any proposed
merger, consolidation or sale or transfer of all or substantially all of the
assets of the Company (a "Sale"), the Holder hereof shall have the right to
convert by delivering a Notice of Conversion to the Company within fifteen (15)
days of receipt of notice of such Sale from the Company. In the event the Holder
hereof shall elect not to convert, the

                                      -6-
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          Company may prepay all outstanding principal and accrued interest on
this Debenture, less all amounts required by law to be deducted, upon which
tender of payment following such notice, the right of conversion shall
terminate.

          14.  The Holder of the Debenture, by acceptance hereof, agrees that
this Debenture is being acquired for investment and that such Holder will not
offer, sell or otherwise dispose of this Debenture or the Shares of Common Stock
issuable upon conversion thereof except under circumstances which will not
result in a violation of the Act or any applicable state Blue Sky or foreign
laws or similar laws relating to the sale of securities.

          15.  This Debenture shall be governed by and construed in accordance
with the laws of the State of New York.

          16.  The following shall constitute an "Event of Default":

               a.   The Company shall default in the payment of principal or
                    interest on this Debenture; or

               b.   The Company shall default in the performance of its
                    obligations under the Subscription Agreement or the Security
                    Agreement; or

               c.   Any of the representations or warranties made by the Company
                    herein, in the Subscription Agreement, or in any certificate
                    or financial or other written statements heretofore or
                    hereafter furnished by the Company in connection with the
                    execution and delivery of this Debenture or the Subscription
                    Agreement shall be false or misleading in any material
                    respect at the time made; or

               d.   The Company fails to issue shares of Common Stock to the
                    Holder or to cause its Transfer Agent to issue shares of
                    Common Stock upon exercise by the Holder of the conversion
                    rights of the Holder in accordance with the terms of this
                    Debenture or the Subscription Agreement, fails to transfer
                    or to cause its Transfer Agent to transfer any certificate
                    for shares of Common Stock issued to the Holder upon
                    conversion of this Debenture and when required by this
                    Debenture, the Subscription Agreement or the Registration
                    Rights Agreement, or fails to remove any restrictive legend
                    or to cause its Transfer Agent to transfer on any
                    certificate or any shares of Common Stock issued to the
                    Holder upon conversion of this Debenture as and when
                    required by this Debenture, the Subscription Agreement or
                    the    Registration Rights Agreement and any such failure
                    shall continue uncured for five (5) business days.

                                      -7-
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               e.   The Company shall fail to perform or observe, in any
                    material respect, any other covenant, term, provision,
                    condition, agreement or obligation of the Company under this
                    Debenture, the Subscription Agreement, the Registration
                    Rights Agreement or the Security Agreement and such failure
                    shall continue uncured for a period of ten (10) days after
                    written notice from the Holder of such failure; or

               f.   The Company shall (1) admit in writing its inability to pay
                    its debts generally as they mature; (2) make an assignment
                    for the benefit of creditors or commence proceedings for its
                    dissolution; or (3) apply for or consent to the appointment
                    of a trustee, liquidator or receiver for its or for a
                    substantial part of its property or business; or

               g.   A trustee, liquidator or receiver shall be appointed for the
                    Company or for a substantial part of its property or
                    business without its consent and shall not be discharged
                    within sixty (60) days after such appointment; or

               h.   Any governmental agency or any court of competent
                    jurisdiction at the instance of any governmental agency
                    shall assume custody or control of the whole or any
                    substantial portion of the properties or assets of the
                    Company and shall not be dismissed within sixty (60) days
                    thereafter; or

               i.   Any money judgment, writ or warrant of attachment, or
                    similar process in excess of Two Hundred Thousand ($200,000)
                    Dollars in the aggregate shall be entered or filed against
                    the Company or any of its properties or other assets and
                    shall remain unpaid, unvacated, unbonded or unstayed for a
                    period of sixty (60) days or in any event later than five
                    (5) days prior to the date of any proposed sale thereunder;
                    or

               j.   Bankruptcy, reorganization, insolvency or liquidation
                    proceedings or other proceedings for relief under any
                    bankruptcy law or any law for the relief of debtors shall be
                    instituted by or against the Company and, if instituted
                    against the Company, shall not be dismissed within sixty
                    (60) days after such institution or the Company shall by any
                    action or answer approve of, consent to, or acquiesce in any
                    such proceedings or admit the material allegations of, or
                    default in answering a petition filed in any such
                    proceeding; or

               k.   The Company shall have its Common Stock suspended or
                    delisted from an exchange or over-the-counter market from
                    trading for in

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               excess of five (5) business days.

Then, or at any time thereafter, and in each and every such case, unless such
Event of Default shall have been waived in writing by the Holder (which waiver
shall not be deemed to be a waiver of any subsequent default) at the option of
the Holder and in the Holder's sole discretion, the Holder may consider this
Debenture immediately due and payable, without presentment, demand, protest or
notice of any kinds, all of which are hereby expressly waived, anything herein
or in any note or other instruments contained to the contrary notwithstanding,
and the Holder may immediately enforce any and all of the Holder's rights and
remedies provided herein or any other rights or remedies afforded by law.

          17.   Upon an Event of Default, the interest rate hereunder shall
increase from 8% to 20% per annum.

          18.   Nothing contained in this Debenture shall be construed as
conferring upon the Holder the right to vote or to receive dividends or to
consent or receive notice as a shareholder in respect of any meeting of
shareholders or any rights whatsoever as a shareholder of the Company, unless
and to the extent converted in accordance with the terms hereof.

                                      -9-
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          IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed by an officer thereunto duly authorized.

Dated:  June 11, 1998

                                    RICH COAST, INC.


                              By:   /s/ James P. Fagan
                                   ------------------------------
                                    Name:
                                    Title:

                                      -10-
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                                   EXHIBIT A


                             NOTICE OF CONVERSION
                             --------------------


                  (To be Executed by the Registered Holder in
                       order to Convert the Debentures)

     The Holder hereby irrevocably elects, as of ______________, 1998 to convert
$________ of Debentures of Rich Coast, Inc. (the "Company") into shares of
Common Stock of  the Company according to the conditions set forth in the
Subscription Agreement dated ______________, 1998.



Date of Conversion:                          _________________________________

Applicable Conversion Price:                 _________________________________

Number of shares of Common Stock:            _________________________________


                                             _________________________________
                                                        Signature


                                             _________________________________
                                                        Print Name


Address for delivery of the Common Stock     _________________________________

                                             _________________________________

                                             _________________________________

Phone                                        _________________________________

Fax                                          _________________________________

Please call me if you need to confirm this facsimile Notice.

Tax I.D. No.:                                _________________________________