TREMONT CORPORATION
NON-NEGOTIABLE PROMISSORY NOTE
<DOCUMENT>
<TYPE>EX-10.5
<SEQUENCE>4
<FILENAME>d89721ex10-5.txt
<DESCRIPTION>NON-NEGOTIABLE PROMISSORY NOTE
<TEXT>
<PAGE>   1
                                                                    EXHIBIT 10.5

                         NON-NEGOTIABLE PROMISSORY NOTE

$1,000,000.00                                                      July 27, 2001
                                                                DENVER, COLORADO

         FOR VALUE RECEIVED, the undersigned, TREMONT CORPORATION, a Delaware
corporation ("Maker"), promises to pay to the order of J. LANDIS MARTIN
("Executive"), at the offices of Maker at 1999 Broadway, Suite 4300, Denver, CO
80202 or such other place as Executive may designate in writing to Maker, the
principal sum of ONE MILLION DOLLARS ($1,000,000.00) of United States funds, or,
if less, so much thereof as may be outstanding from time to time, plus interest
as hereinafter provided.

         Maker hereby promises to pay to Executive the unpaid principal amount
in five (5) equal annual installments on June 12 of each year commencing on June
12, 2002, with all unpaid principal and interest due and payable on June 12,
2006 (the "Maturity Date"); provided, however, if the payment of such amount at
such time would not be deductible to Maker for tax purposes under the provisions
of Section 162(m) of the Internal Revenue Code of 1986, as amended, or any
successor provision, Maker may defer such payment until the earliest time at
which the payment of such amount would be deductible by Maker. Maker, acting
through its Management Development & Compensation Committee, may elect, in its
sole discretion, to make payment of all or any portion of the principal prior to
the Maturity Date without penalty or premium.

         Maker hereby promises to pay interest on the unpaid principal amount
hereof at a rate per annum equal to seven percent (7.0%) from June 12, 2001 up
to and including the date of payment. Interest accrued on the unpaid principal
shall be payable at the time of payment to Executive of each annual installment
of principal pursuant to the immediately preceding paragraph. Interest accrued
pursuant to this paragraph shall compound on a semi-annual basis on January 1
and July 1 and shall be computed for the actual number of days elapsed on the
basis of a year consisting of 365 or 366 days, as applicable. Overdue principal
and, to the extent permitted by law, overdue interest, shall bear interest
payable on DEMAND at a rate of ten percent (10%) per annum from the date payment
was due until and including the date actually paid (it being recognized that any
principal or interest the payment of which is deferred by Maker pursuant to the
proviso of the immediately preceding paragraph for tax reasons shall
nevertheless be regarded as overdue).

         In no event shall the amount of interest due or payable hereunder
exceed the maximum rate of interest allowed by applicable law, and in the event
any such payment is inadvertently made by Maker or inadvertently received by
Executive, then such excess sum shall be credited as a payment of principal,
unless Maker shall notify Executive in writing that it elects to have such
excess sum returned forthwith. It is the express intent of the parties that
Maker not pay and Executive not receive, directly or indirectly in any manner
whatsoever, interest in excess of that which may legally be paid by Maker under
applicable law.



                                       1
<PAGE>   2


         Maker shall withhold from any amounts paid to Executive pursuant to
this Note, in the year such amount is paid to Executive, or from any salary,
bonus or other compensatory payment made to Executive as Maker in its sole
discretion may determine, such amounts as are required by law to be withheld
pursuant to any applicable withholding requirements.

         All parties now or hereafter liable with respect to this Note, whether
Maker, any guarantor, endorser, or any other person, hereby waive presentment
for payment, demand, notice of non-payment or dishonor, protest and notice of
protest.

         No delay or omission on the part of Executive or any holder hereof in
exercising his or its rights under this Note or course of conduct relating
thereto, shall operate as a waiver of such rights or any other right of
Executive or any holder hereof, nor shall any waiver of any such right or rights
on any one occasion be deemed a bar to, or waiver of, the same right or rights
on any future occasion.

         Maker promises to pay all reasonable costs of collection, including
attorneys' fees and expenses, should this Note be collected by or through an
attorney-at-law or under advice therefrom.

         Time is of the essence of this Note.

         This Note is non-negotiable.

         This Note shall be construed in accordance with and governed by the
internal laws of the state of Colorado.

         IN WITNESS WHEREOF, Maker has executed this Note on the day and year
first above written, but with effect as of June 12, 2001.


                                             MAKER:

                                             TREMONT CORPORATION




                                             By: /s/Robert E Musgraves
                                                --------------------------------

                                             Its: Vice President
                                                 -------------------------------



                                       2

</TEXT>
</DOCUMENT>
