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                                                                    EXHIBIT 4.27


                                   KFX INC.


                133,333 Warrants Each to Purchase One Share of
                           Common Stock of KFx Inc.

                                                            Warrants to Purchase
                                                                  133,333 Shares


          THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
     REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR ANY
     OF THE LAWS OF ANY STATE AND HAVE BEEN ISSUED PURSUANT TO AN EXEMPTION FROM
     REGISTRATION UNDER THE ACT. THE SECURITIES REPRESENTED BY THIS CERTIFICATE
     MAY NOT BE OFFERED, SOLD OR TRANSFERRED EXCEPT IF (A) COVERED BY AN
     EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT AND REGISTERED OR QUALIFIED
     UNDER APPLICABLE STATE SECURITIES LAWS, OR (B) THE CORPORATION HAS BEEN
     FURNISHED WITH AN OPINION OF COUNSEL REASONABLY ACCEPTABLE TO THE
     CORPORATION TO THE EFFECT THAT NO REGISTRATION OR QUALIFICATION IS LEGALLY
     REQUIRED FOR SUCH TRANSFER.

     FOR VALUE RECEIVED, KFx Inc., a Delaware corporation (the "Company"),
hereby certifies that Dr. James R. Schlesinger, an individual or his registered
assigns as permitted herein (the "Holder") is entitled, subject to the
provisions of this Warrant Certificate, to purchase from the Company, at the
times specified herein, 133,333 fully paid and non-assessable shares of Common
Stock of the Company, par value $.001 per share (the "Common Stock"), at a
purchase price per share equal to the Exercise Price (as hereinafter defined)
(the "Warrants"). The number of shares of Common Stock to be received upon the
exercise of the Warrants are subject to adjustment from time to time as
hereinafter set forth.

                                   ARTICLE I

                                  DEFINITIONS

     The following terms, as used herein, have the following meanings:

     "Act" means the Securities Act of 1933.

     "Board" means the board of directors of the Company.

     "Business Day" means any day except a Saturday, Sunday or other day on
which commercial banks in the City of New York are authorized by law to close.

     "Commission" means the Securities and Exchange Commission.
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     "Common Stock" means the Company's common stock, $.001 par value per share.

     "Exercise Price" means $3.65 per Warrant Share, such Exercise Price to be
adjusted from time to time as provided herein.

     "Expiration Date" means the earlier of (i) 5:00 p.m. Denver, Colorado time
on November 29, 2006, and (ii) the date of its exercise in full.

     "Person" means an individual, a partnership, a corporation, a limited
liability company, a trust, a joint venture, an unincorporated organization and
a government or any department or agency thereof.

     "Warrant Shares" means the shares of Common Stock deliverable upon exercise
of the Warrants, as the number of such shares shall be adjusted from time to
time as provided herein, provided that if there is a change such that the
securities issuable upon exercise of the Warrants are issued by an entity other
than the Company or there is a change in the class of securities so issuable,
then the term "Warrant Shares" will mean the shares of the security issuable
upon exercise of the Warrants if such security is issuable in shares, or will
mean the smallest units in which such security is issuable if such security is
not issuable in shares.

                                  ARTICLE II

     Section 2.01.  Exercise of Warrants.

     (1) The Holder is entitled to exercise the Warrants in whole or in part at
any time, or from time to time, until the Expiration Date or, if such day is not
a Business Day, then on the next succeeding day that shall be a Business Day. To
exercise the Warrants, the Holder shall execute and deliver to the Company a
Warrant Exercise Notice substantially in the form annexed hereto, together with
this Warrant Certificate and the payment of the applicable Exercise Price. Upon
such delivery and payment, the Holder shall be deemed to be the holder of record
of the Warrant Shares subject to such exercise, notwithstanding that the stock
transfer books of the Company shall then be closed or that certificates
representing such Warrant Shares shall not then be actually delivered to the
Holder.

     (2) The Exercise Price may be paid in cash or by certified or official bank
check or bank cashier's check payable to the order of the Company or by any
combination of such checks. In addition, the Holder of this Warrant may exercise
this Warrant by surrendering it to the Company to purchase a number of shares of
Common Stock equal to the number of such shares then purchasable upon exercise
hereof less the number of such shares equal to the quotient of the aggregate
Exercise Price of all such shares underlying this Warrant divided by the Fair
Market Price per Share. Fair Market Price per Share shall mean the average of
the closing sales prices, if available, or the average of the bid and asked
prices for the Common Stock (or its successor), on the principal market therefor
for the five trading days preceding the day which is one business day prior to
the day of exercise, or if no such price is available, as determined by the
Board. The Company shall pay any and all documentary, stamp or similar issue or
transfer taxes payable in respect of the issue or delivery of the Warrant
Shares.

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     (3) If the Holder exercises the Warrants in part, this Warrant Certificate
shall be surrendered by the Holder to the Company and a new Warrant Certificate
of the same tenor and for the unexercised number of Warrant Shares shall be
executed by the Company. The Company shall register the new Warrant Certificate
in the name of the Holder or in such name or names of its transferees as may be
directed in writing by the Holder and deliver the new Warrant Certificate to the
Person or Persons entitled to receive the same.

     (4) Upon surrender of this Warrant Certificate in conformity with the
foregoing provisions, the Company shall transfer to the Holder of this Warrant
Certificate appropriate evidence of ownership of the shares of Common Stock or
other securities or property (including any money) to which the Holder is
entitled, registered or otherwise placed in, or payable to the order of, the
name or names of the Holder or such transferee as may be directed in writing by
the Holder, and shall deliver such evidence of ownership and any other
securities or property (including any money) to the Person or Persons entitled
to receive the same, together with the amount in cash in lieu of any fraction of
a share as provided in Section 2.03 below.

     Section 2.02. Restrictive Legend. Certificates representing shares of
Common Stock issued pursuant to the Warrants shall bear a legend substantially
in the form of the legend set forth on the first page of this Warrant
Certificate.

     Section 2.03. Fractional Shares. No fractional shares or scrip representing
fractional shares shall be issued upon the exercise of the Warrants and in lieu
of delivery of any such fractional share upon any exercise hereof, the Company
shall pay to the Holder an amount in cash equal to such fraction multiplied by
the then current market price per share of Common Stock.

     Section 2.04. Loss or Destruction of Warrant. Upon receipt by the Company
of evidence satisfactory to it (in the exercise of its reasonable discretion) of
the loss, theft, destruction or mutilation of this Warrant Certificate, and (in
the case of loss, theft or destruction) of reasonably satisfactory
indemnification, and upon surrender and cancellation of this Warrant
Certificate, if mutilated, the Company shall execute and deliver a new Warrant
Certificate of like tenor and date.

     Section 2.05. Forfeiture. Except as otherwise provided in this Warrant, the
Warrants may be exercised at any time through the close of business on November
29, 2006.

     Section 2.06. Effect of Reorganization, Reclassification, Consolidation,
Merger or Sale. If at any time while this Warrant is outstanding there shall be
any reorganization or reclassification of the capital stock of the Company
(other than a stock split, stock dividend or other subdivision or combination of
shares) or any consolidation or merger of the Company with another corporation
(other than a consolidation or merger in which the Company is the surviving
entity and which does not result in any change in the Common Stock), or any sale
or other disposition by the Company of all or substantially all of its assets to
any other corporation, the Holder shall thereafter upon exercise of this Warrant
be entitled to receive the number of shares of stock or other securities or
property of the Company, or of the successor corporation resulting from such
consolidation or merger, as the case may be, to which the Warrant Shares
deliverable upon the exercise of this Warrant would have been entitled upon such
reorganization,

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reclassification of capital stock, consolidation, merger, sale or other
disposition if this Warrant had been exercised immediately prior to such
reorganization, reclassification of capital stock, consolidation, merger, sale
or other disposition. In any such case, appropriate adjustment (as determined by
the Board) shall be made in the application of the provisions set forth in this
Warrant with respect to the rights and interests thereafter of the Holder to the
end that the provisions set forth in this Warrant (including those relating to
adjustments of the Exercise Price and the number of shares issuable upon the
exercise of this Warrant) shall thereafter be applicable, as near as reasonably
may be, in relation to any shares or other property thereafter deliverable upon
the exercise hereof as if this Warrant had been exercised immediately prior to
such reorganization, reclassification of capital stock, consolidation, merger,
sale or other disposition and the Holder hereof had carried out the terms of the
exchange as provided for by such reorganization, reclassification of capital
stock, consolidation or merger.

     Section 2.07. Adjustments for Stock Events. If at any time there shall
occur any stock split, stock dividend, reverse stock split or other subdivision
or combination of the Company's Common Stock (a "Stock Event"), then the number
of shares of Common Stock to be received by the holder of this Warrant shall be
appropriately adjusted such that the proportion of the number of shares issuable
hereunder to the total number of shares of the Company (on a fully diluted
basis) prior to such Stock Event is equal to the proportion of the number of
shares issuable hereunder after such Stock Event to the total number of shares
of the Company (on a fully-diluted basis) after such Stock Event. No adjustment
to the Exercise Price shall be made in connection with any adjustment of the
number of shares of Common Stock receivable upon exercise of this Warrant,
except that the Exercise Price shall be proportionately decreased or increased
upon the occurrence of any Stock Event; however, in no event shall the Exercise
Price be less than the par value of the Common Stock.

     Section 2.08. Reservation of Common Stock. The Company will at all times
reserve and keep available for issuance upon the exercise of the Warrant such
number of its authorized but unissued shares of Common Stock as will be
sufficient to permit the exercise in full of the Warrant, and when issued upon
such exercise shall be validly issued, fully paid and nonassessable.

                                  ARTICLE III

                               NO VOTING RIGHTS

     Prior to the exercise of any Warrant, the Holder shall not, by virtue
hereof, be entitled to any rights as a stockholder of the Company, including,
without limitation, the right to vote, to receive dividends or other
distributions, to exercise any preemptive rights or to receive any notice of
meeting of stockholders or any notice of any proceedings of the Company except
as may be specifically provided for herein.

                                  ARTICLE IV

                           TRANSFER; REPRESENTATIONS

          (a) Subject to the transfer conditions referred to in paragraph (b)
     below, this Warrant and all rights hereunder are transferable, in whole or
     in part, without charge to

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     the Holder upon completion of the form of Assignment attached hereto as
     Exhibit B and surrender of this Warrant, together with such assignment, at
     the principal office of the Company.

          (b) The Holder of this Warrant acknowledges and represents:

              (i)    that neither this Warrant nor the Warrant Shares have been
          registered under the Act, or any state securities law and agrees not
          to sell, pledge, distribute, offer for sale, transfer or otherwise
          dispose of this Warrant or any Warrant Shares issued upon its exercise
          in the absence of (A) an effective registration statement as to this
          Warrant or such Warrant Shares under the Act (or any similar statute
          then in effect) or any state securities law, or (B) an opinion of
          counsel for the Company to the effect that such registration is not,
          under the circumstances, required.

              (ii)   THE OFFER AND SALE OF THE SECURITIES EVIDENCED BY THIS
          CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE ACT, AND SUCH
          SECURITIES MAY NOT BE SOLD OR TRANSFERRED UNLESS THERE IS AN EFFECTIVE
          REGISTRATION STATEMENT UNDER SUCH ACT COVERING SUCH SALE OR TRANSFER
          OR THE COMPANY RECEIVES AN OPINION OF COUNSEL (WHICH MAY BE COUNSEL
          FOR THE COMPANY) STATING THAT SUCH SALE OR TRANSFER IS EXEMPT FROM THE
          REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACT.

              (iii)  The Holder is acquiring this Warrant and the Warrant
          Shares for its own account for investment and not with a view to, or
          for sale in connection with, any distribution thereof; nor with any
          present intention of distributing or selling the same.

              (iv)   The Holder has made detailed inquiry concerning the
          Company, its business and its personnel; the officers of the Company
          have made available to the Holder any and all written information
          which it has requested and have answered to the Holder's satisfaction
          all inquiries made by the Holder, and the Holder has sufficient
          knowledge and experience in investing in companies similar to the
          Company so as to be able to evaluate the risks and merits of its
          investment in the Company and is able financially to bear the risks
          thereof.

          (c) The Holder understands that the Company proposes to issue and
     deliver this Warrant and the Warrant Shares to the Holder pursuant to this
     Agreement without compliance with the registration requirements of the Act;
     that for such purpose the Company will rely upon the representations,
     warranties, covenants and agreements contained herein; and that such non-
     compliance with registration is not permissible unless such representations
     and warranties are correct and such covenants and agreements performed. The
     Holder is an "accredited investor" as such term is defined in Rule 501
     under the Act.

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          (d) The Holder understands that, under existing rules of the
     Commission, the Holder may be unable to sell this Warrant and the Warrant
     Shares except to the extent that this Warrant and the Warrant Shares may be
     sold (i) pursuant to an effective registration statement covering such
     securities pursuant to the Act or (ii) in a bona fide private placement to
     a purchaser who shall be subject to the same restrictions on any resale or
     (iii) subject to the restrictions contained in Rule 144 under the Act.

          (e) The Holder (either alone or together with its advisors) has
     sufficient knowledge and experience in financial and business matters so as
     to be capable of evaluating the merits and risks of its investment in this
     Warrant and the Warrant Shares and the Holder is capable of bearing the
     economic risks of such investment.

                                   ARTICLE V

                                 NO IMPAIRMENT

     The Company will not, by amendment of its charter or through
reorganization, consolidation, merger, dissolution, sale of assets or any other
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms of this Warrant, but will at all times in good faith assist in the
carrying out of all such terms and in the taking of all such action as may be
necessary or appropriate in order to protect the rights of the Holder of this
Warrant against impairment.

                                  ARTICLE VI

                             LIQUIDATING DIVIDENDS

     If the Company pays a dividend or makes a distribution on the Common Stock
payable otherwise than in cash out of earnings or earned surplus (determined in
accordance with generally accepted accounting principles), except for a stock
dividend payable in shares of Common Stock (a "Liquidating Dividend"), then the
Company will pay or distribute to the holder of this Warrant, upon the exercise
hereof, in addition to the Warrant Shares purchased upon such exercise, the
Liquidating Dividend which would have been paid to such holder if he had been
the owner of record of such shares of Common Stock immediately prior to the date
on which a record is taken for such Liquidating Dividend or, if no record is
taken, the date as of which the record holders of Common Stock entitled to such
dividend or distribution are to be determined.

                                  ARTICLE VII

                         NOTICES OF RECORD DATE, ETC.

     In case:

          (a) the Company shall take a record of the holders of its Common Stock
     (or other stock or securities at the time deliverable upon the exercise of
     this Warrant) for the purpose of entitling or enabling them to receive any
     dividend or other distribution, or to receive any other right, or

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          (b) of any capital reorganization of the Company, any reclassification
     of the capital stock of the Company, any consolidation or merger of the
     Company with or into another corporation (other than a consolidation or
     merger in which the Company is the surviving entity), or any transfer of
     all or substantially all of the assets of the Company, or

          (c) of the voluntary or involuntary dissolution, liquidation or
     winding-up of the Company,

     then, and in each such case, the Company will mail or cause to be mailed to
     the Holder of this Warrant a notice specifying as the case may be, (i) the
     date on which a record is to be taken for the purpose of such dividend,
     distribution or right, and stating the amount and character of such
     dividend, distribution or right, or (ii) the effective date on which such
     reorganization, reclassification, consolidation, merger, transfer,
     dissolution, liquidation or winding-up is to take place, and the time, if
     any is to be fixed, as of which the holders of record of Common Stock (or
     such other stock or securities at the time deliverable upon the exercise of
     this Warrant) shall be entitled to exchange their shares of Common Stock
     (or such other stock or securities) for securities or other property
     deliverable upon such reorganization, reclassification, consolidation,
     merger, transfer, dissolution, liquidation or winding-up. Such notice shall
     be given at least ten (10) days prior to the record date or effective date
     for the event specified in such notice.

                                 ARTICLE VIII

                                 MISCELLANEOUS

     Section 8.01. Amendment and Waiver. The provisions of the Warrant may be
amended and the Company may take any action herein prohibited, or omit to
perform any act herein required to be performed by it upon the written consent
of the holders of a majority of the outstanding Warrants exercisable for a
majority of the Warrant Shares.

     Section 8.02. Notices. Any notices required to be sent to the Holder will
be delivered to the address of the Holder shown on the books of the Company. All
notices referred to herein will be delivered in person, sent by first-class
mail, postage prepaid, or by recognized express courier (such as Federal
Express). Notice will be deemed to have been given upon personal delivery, one
business day after deposit with an express courier or two business days after
deposit in the mail.

     Section 8.03. Descriptive Headings; Governing Law. The descriptive headings
of the paragraphs of this Warrant are inserted for convenience only and do not
constitute a part of this Warrant. The construction, validity and interpretation
of this Warrant will be governed by the laws of the State of Delaware.

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     IN WITNESS WHEREOF, the Company has caused this Warrant to be signed and
sealed by its duly authorized officers under its corporate seal this 29th day of
November, 2001.

                                           KFx Inc.

                                           By __________________________________
                                           Name:  ______________________________
                                           Title: ______________________________

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                                   EXHIBIT A

                            WARRANT EXERCISE NOTICE

              (To be executed only upon exercise of the Warrants)


To:  KFx Inc.

     The undersigned irrevocably exercises the Warrants for the purchase of
__________ shares (the "Shares") of Common Stock, par value $.001 per share, of
KFx Inc. (the "Company") and agrees to make payment therefor [in the amount of
$______________] [in accordance with the cashless exercise provisions of Section
2.01(2) of the within Warrant Certificate], all on the terms and conditions
specified in the within Warrant Certificate, surrenders this Warrant Certificate
and all right, title and interest therein to the Company and directs that the
Shares deliverable upon the exercise of the Warrants be registered or placed in
the name and at the address specified below and delivered thereto.

Dated: ___________________, 20__.



                                            ____________________________________
                                            (Signature of Owner)

                                            ____________________________________
                                            (Street Address)

                                            ____________________________________
                                            (City)        (State)     (Zip Code)

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Securities and/or check to be issued to:


Please insert social security or identifying number:


Name:


Street Address:


City, State and Zip Code:


Any unexercised portion of the Warrants evidenced by the within Warrant
Certificate to be issued to:


Please insert social security or identifying number:


Name:


Street Address:


City, State and Zip Code

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                                   EXHIBIT B

                                   ASSIGNMENT


     FOR VALUE RECEIVED, _______________ hereby sells, assigns and transfers all
of the rights of the undersigned under the within Warrant, with respect to the
number of shares of Common Stock covered thereby set forth hereinbelow unto:

     Name of Assignee           Address          No. of Shares of
     ----------------           -------          Common Stock
                                                 ------------

     ____________________   __________________   ____________
                            __________________
                            __________________



Date:__________________     Name         __________________________
                                         __________________________
                            Signature    __________________________
                            Witness      __________________________


     This Assignment must be completed and sent to:

                    KFx Inc.
                    3300 East First Avenue
                    Suite 290
                    Denver, CO 80206

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