LEASE


     THIS LEASE is made and entered into by and between Henry G. Luken, III, a
Tennessee resident, herein called "Owner", and Covista, Inc., a New Jersey
company, herein called "Tenant".

     For acknowledged consideration, Owner leases to Tenant and Tenant rents
from Owner the real property located at 4801 Highway 58 in the City of
Chattanooga, County of Hamilton, State of Tennessee, being the property more
fully described in Exhibit A, attached hereto, together with all improvements
and additions thereon, herein called the "premises"; and Owner and Tenant
agree as follows:

                                 SECTION 1
                      TERM AND OPTION TO EXTEND TERM

     1.1   The term of this lease shall be for five (5) years beginning on the
1st day of September, 2001.

     1.2   Tenant shall have the option to extend the term of this lease for
an additional five (5) years, this option to be exercised by giving written
notice to Owner at least ninety (90) days prior to the expiration of the then
current term under this lease.  During the extended term, the provisions of
this lease shall remain the same except that the amount of rent shall be
increased if and to the extent provided by this lease.

     1.3   Owner shall not be liable for failure to give possession of the
premises to Tenant upon the effective date of this lease if the failure occurs
because the premises are not ready for occupancy, or are being held over by a
prior tenant or are otherwise in the wrongful possession of another party, or
are not available for any other reason.  In such event the rent shall not
begin until possession is given to or made available to Tenant, and the term
of this lease shall not be extended by such delay in delivering possession.
If the delay in possession exceeds thirty (30) days, either Owner or Tenant,
by written notice to the other, may terminate this lease and neither party
shall have nor incur any liability or obligation to the other party as a
result of such termination.

                           SECTION 2
                             RENT

     2.1   During the lease Tenant shall pay and Owner shall accept a rental
as follows:

           Rental Period                                   Rent
           -------------                                   ----
  September 1, 2001 - August 30, 2002                $7,200 per month
  September 1, 2002 - August 30, 2003                $9,600 per month
  September 1, 2003 - August 30, 2004               $12,000 per month

The rental for each month beginning on September 1, 2004 and the rental for
any extended term if the term of the of this lease is extended beyond the
original term, shall be Twelve Thousand Dollars ($12,000.00) per month or, if
greater, the amount determined by multiplying the rental for each month of the
prior year by a fraction, the numerator of which is the Consumers Price Index
United States - All Items, for January of the fourth and fifth year or each
year of the extended term, and the denominator of which is such index figure
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on the same base, for January of 2003, provided that such fraction shall never
be less than one (1).

     2.2     In addition to these rental payments, Tenant shall pay when due,
as additional rent, all other amounts to be paid by Tenant under this lease.

     2.3     It is the intention of Owner and Tenant that the rent paid under
this lease shall be net to Owner and that each year during the term of the
lease all costs, expenses and obligations of every kind relating to the
premises (except as otherwise specifically provided in this lease) which may
arise or become due during the term of this lease shall be paid by Tenant, and
that Owner shall be indemnified by Tenant against such costs, expenses and
obligations.

     2.4     All payments of rent shall be made by Tenant to Owner without
notice or demand, at such place within the United States as Owner may from
time to time designate in writing.  For the present Owner designates Owner's
address stated in or pursuant to the Notices provisions of this lease as the
place for making the payments of rent.  All rents shall be payable in legal
tender of the United States as the same is then constituted.

     2.5     A late fee will accrue at the rate of twelve percent (12%) per
annum on all delinquent rent and other amounts due from Tenant.  Such late fee
shall be immediately due and payable as additional rent under this lease.

                            SECTION 3
                            UTILITIES

     Tenant shall pay for all utilities, including but not limited to water,
gas, electricity, sewage disposal, and heat and other utilities used on the
premises during the term of this lease and shall pay all charges of any party
furnishing water pressure for any sprinkler system on the premises.

                            SECTION 4
                              TAXES

     4.1     Tenant shall pay all real property taxes, assessments and
governmental levies on the premises.

     4.2     Tenant shall pay any license tax or other tax on the business
activity of Tenant and on property belonging to Tenant and situated on the
premises, and any real property tax attributable to any additions or
improvements added to the premises by Tenant.

                             SECTION 5
                         TAX CERTIFICATION

     Owner hereby certifies that Owner is not a non-resident alien, or foreign
corporation, a foreign partnership, a foreign trust or a foreign estate (as
those terms are defined in the Internal Revenue Code and Income Tax
Regulations); that Owner's Social Security number or Federal Income Tax number
and home or office address are as shown in this Lease.  Owner acknowledges
that this certification may be disclosed to the Internal Revenue Service
pursuant to federal law.


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                              SECTION 6
               REPAIRS, MAINTENANCE AND IMPROVEMENTS

     6.1     Tenant shall at its own expense keep the premises clean, neat and
free of all trash or rubbish.

     6.2     Tenant shall, at Tenant's expense, maintain and keep in good
repair the interior of the premises including but not limited to the ceiling,
light fixtures, interior walls and floors, all doors, windows, glass, and
plumbing, all water and gas pipes, and sprinkler system, if any.

     6.3     Owner shall, at Owner's expense, make all necessary exterior
structural repairs including but not limited to the roof, gutters and
downspouts, and the outside walls of the premises, and the exterior of all
improvements on the premises.

     6.4     The parking lot paving, parking areas, sidewalks, lawns and
landscaping shall be maintained by Tenant.

     6.5     Owner shall, at its own expense, make all structural repairs and
restorations, whether or not interior or exterior, ordinary or extraordinary,
recurring or nonrecurring in nature, and shall keep the premises in good
repair, ordinary wear and tear, and damage by reason of natural causes or fire
excepted.

     6.6     Tenant may make reasonable alterations, additions and
improvements to the premises, including the erection of signs, at Tenant's
expense but only with the prior consent in writing of Owner.  All such work
shall be in compliance with all applicable federal, state and local laws and
regulations, including those pertaining to access to public accommodations,
and Owner's consent to make such alterations will not relieve Tenant of such
responsibility.  All alterations, additions or improvements made by either of
the parties, except movable office furniture and movable business fixtures and
equipment put in at the expense of Tenant, shall inure to the benefit of Owner
and shall belong to Owner absolutely as soon as made or installed.  Tenant
may, if Tenant is not in default on any of the terms and conditions of this
lease, remove at the termination of the lease any movable office furniture or
movable business fixtures or equipment purchased or provided by Tenant that
may be moved without damage to the building, provided that Owner is notified
before the termination date that this right will be exercised, as to described
fixtures or equipment.  If Tenant causes any damage to the premises in
removing Tenant's property, Tenant shall pay for all repairs.

     6.7     Upon termination of this lease Tenant shall return the premises
to Owner in the same condition as when received, ordinary wear and tear
excepted.

                               SECTION 7
                  LIABILITY INSURANCE AND INDEMNITY

     7.1     In addition to any insurance which Tenant deems necessary to
protect Tenant's interests, Tenant shall,  at Tenant's expense, secure and
maintain during the term and any extended term of this lease, liability
insurance with an insurance company satisfactory to Owner, with Tenant and
Owner as named insureds, in amounts not less than $1,000,000 per person,
$1,000,000 per occurrence for all persons and $500,000 for property damage.
Tenant may, in lieu of delivering the original policies of insurance, deliver
to Owner insurance company certificates evidencing the coverage.  The
requirement of the liability insurance notwithstanding, Owner shall not be
<PAGE>
liable for any injury or damage to persons or property occurring in or about
the premises, and Tenant shall save Owner harmless from responsibility for any
and all such injuries and for all such damage arising from any cause
whatsoever.  Owner shall be under no liability to Tenant arising from any
discontinuance of heat or water, or both, caused by accident, by breakage, by
strike, or otherwise.  Owner shall not be liable for loss of or damage to the
property of Tenant caused by rain, snow, water or steam that may leak into or
flow from any part of the premises as a result of any defect in the roof or
plumbing or any cause whatsoever, or for loss or damage caused by the handling
of electric wires or lights.

     7.2     If the Tenant shall fail, refuse or neglect to obtain such
insurance or to maintain the same, and furnish the Owner with proof of the
same upon demand, the Owner shall have the right, in addition to other
remedies, to procure such insurance and to add the cost thereof to any rental
or other sums payable under this lease, and the amount thereof shall be
payable to the Owner on demand with lawful interest thereon.

     7.3     Tenant shall cause any policy or certificate of insurance
required by this lease to be issued promptly upon any renewal or extension of
such coverage showing the Owner as insured.

                             SECTION 8
                 CASUALTY INSURANCE AND CASUALTY DAMAGE

     8.1     Tenant shall secure and constantly maintain, at Tenant's expense,
insurance against loss or damage by fire and such other casualty risks and
hazards, including but not limited to lightning, flood and windstorm, as are
insurable under present and future standard forms of extended coverage
insurance policies, upon the buildings and other improvements erected on the
premises.

      Any such policy or policies of insurance shall name Owner as the
insured, and shall otherwise be in a form approved by Owner.

     8.2     Tenant shall furnish the original of such policy to Owner or
insurance company certificates evidencing the coverage.

     8.3     If the premises are so used that casualty insurance cannot be
secured, Tenant will become the insurer, and Owner may cancel this lease by
giving written notice to Tenant.

     8.4     If the premises are rendered totally or substantially
untenantable by fire or other casualty, this lease, at the option of Owner or
Tenant exercised in writing within thirty (30) days of the date of the fire or
casualty, shall terminate; otherwise Owner shall restore the premises as
rapidly as sound business judgment permits.

     8.5     If the premises are rendered totally or substantially
untenantable, and are to be restored, rent will abate during restoration and
the term of this Lease shall be extended for a period of time equal to the
period of time of such restoration.  If the premises are so damaged that
Tenant can continue to occupy the same or part of same, the rent shall abate
pro rata only and Owner shall repair the damage as rapidly as sound business
judgment permits.

     8.6     The Owner shall have the sole and exclusive right to the proceeds
of any insurance covering the premises whether provided by Owner or Tenant.
If any restoration or repair work is to be done, the proceeds of any insurance
<PAGE>
shall be provided to Owner for that purpose.  Any insurance proceeds in excess
of the cost of such restoration or repairs, or all of the insurance proceeds
if the premises are not to be restored or repaired pursuant to the provisions
of this lease, shall be the sole property of and paid to Owner, and Tenant
shall have no interest therein.  In the event of a mortgage or encumbrance on
the premises which requires that the insurance proceeds be used to retire or
pay such mortgage or encumbrance, then Owner shall have no obligation to
rebuild or repair and this lease may be terminated upon notice to Tenant
following any fire or casualty.

     8.7     Tenant shall carry and maintain at its own expense such insurance
as Tenant deems necessary or advisable to protect its interests under this
lease with regard to Tenant's fixtures, equipment and merchandise located at
the premises.

                            SECTION 9
                       WARRANTIES OF OWNER

     9.1     Owner warrants and covenants that Owner is lawfully able to
demise the premises and that Tenant, on paying the rental herein provided and
performing the other covenants and conditions herein contained, shall have
quiet and peaceful possession of the premises during the lease term.  No
provisions of this lease are intended to warrant or imply that Owner has any
greater right or interest than stated in this paragraph.

     9.2     Except as otherwise specifically provided in this lease, Tenant
is acquainted with the entire premises and accepts the same in their present
condition.  Tenant assumes responsibility for the safety of the premises, for
the suitability of the premises for Tenant's use, and for the premises'
compliance with the requirements of Title III of the American with
Disabilities Act of 1991.

     9.3     Owner makes no other warranties express or implied.

                            SECTION 10
                     SUBLEASE OR ASSIGNMENT

       Neither Tenant nor any court or officer thereof or receiver or trustee
in bankruptcy shall sublease, assign, or transfer the premises or any interest
in this lease without the consent in writing of Owner, which shall not be
unreasonably withheld.  Landlord may withhold consent if the premises is not
currently a place of public accommodation and the subletting or assignment
will cause it to be used at such.  In the event of a sublease or assignment,
Tenant shall always remain liable for any default of a subtenant or assignee.
The receipt by Owner of rents from any assignee, subtenant or occupant shall
not be deemed to be a waiver of these provisions.

                           SECTION 11
                         USE OF PREMISES

     The premises shall during the term of this lease be used only for
offices, and no part of the premises or improvements thereon shall be used in
any manner whatsoever for a purpose in violation of the laws of the United
States or the state in which the premises are located or any other applicable
ordinance, regulation or law.  Tenant shall comply with all laws, ordinances,
regulations or orders enacted or passed during the term of this lease
applicable to the premises.

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                            SECTION 12
                           CONDEMNATION

     If at any time a substantial part or all of the premises be taken for any
public or quasi-public use under any statute or by right of eminent domain or
by private purchase in lieu thereof by a body vested with the power of eminent
domain, this lease shall continue until the date of the taking, at which time
this lease shall terminate and Tenant shall have no rights in any award or
purchase price paid by reason of the taking.  In the event a condemnation or
purchase takes place and the premises continue to be tenantable for Tenant's
purposes, the rent shall be abated pro rata, Tenant shall have no rights in
any award or purchase price paid by reason of the taking, and the lease shall
continue otherwise in full force and effect.  The termination of this lease or
the abatement of rent by reason of the condemnation or purchase shall be
without prejudice to the rights of either Owner or Tenant (to the extent
Tenant has an independent claim) to recover compensation and damage caused by
the condemnation or taking from the condemner or taker.  Neither Owner nor
Tenant shall have any rights in any award made to the other by reason of such
condemnation or taking.

                              SECTION 13
                      ENVIRONMENTAL COMPLIANCE

     13.1   Tenant, at Tenant's Expense, shall comply with all Environmental
Laws (as defined below) pertaining to Tenant's business use and occupancy of
the Premises and shall promptly advise Owner of any Notice, as defined herein.
Tenant hereby agrees to and does indemnify and holds Owner harmless from and
against any and all liability, obligations, losses, damages, penalties,
claims, clean-up costs, fines, civil penalties and actions, suits, including
legal fees imposed on, incurred by, or reserved against Owner arising out of
the existence or presence of any "Regulated Substance", as defined herein, on,
under or from the Premises from and after the commencement of the initial term
of this lease ("Commencement Date") arising out of Tenant's occupancy and use
of the Premises; and any liability, claims, or damages in any way related to
or arising out of the removal, treatment, storage, disposal, disposition,
mitigation, clean-up or remedying of by Tenant of Regulated Substances on the
Premises.  Notwithstanding anything herein to the contrary, Owner agrees that
Tenant has no obligation to and does not indemnify Owner for any claims or
damages due to any Regulated Substances existing or present on the Demised
Premises prior to the Commencement Date or arising out of the acts of third
parties not under Tenant's control.

     13.2  For the purposes of this Section 14, the following terms shall have
the meanings set forth herein:

           (a)  "Environmental Laws" means any applicable federal, state,
regional, county or local laws, statutes, rules, regulations or ordinances,
including, but not limited to, the Comprehensive Environmental Response,
Compensation and Liability Act of 1980, as amended by the Superfund Amendments
and Reauthorization Act of 1986, 42 U.S.C. Section 9601 et seq. ("CERCLA"),
the Resource Conservation and Recovery Act of 1976, as amended by the
Hazardous and Solid Waste Amendments of 1984, 42 U.S.C. Section 6901 et seq.
("RCRA"), the Federal Water Pollution Control Act, as amended by the Clean
Water Act of 1977, 33 U.S.C. Section 1251 et seq ("CWA"), the Toxic Substances
Control Act of 1976, 15 U.S.C. Section 2601 et seq. ("TSCA"), the Emergency
Planning and Community Right-To-Know Act of 1986, as amended, 42 U.S.C.
Section 11001 et seq. ("Sara Title III"), the Clean Air Act of 1986, as
amended, 42 U.S.C. Section 7401 et seq. ("CAA"), the National Environmental
<PAGE>
Policy Act and Harbors Act of 1899, 33 U.S.C. Section 401 et seq. ("RHA"), the
Occupational Safety and Health Act of 1970, 29 U.S.C. Section 651 et seq.
("OSHA"), and the Safe Drinking Water Act of 1974, as amended, 42 U.S.C.
Section 300(f) et seq. ("SDWA"), and any and all rules, regulations and
guidance documents promulgated or published thereunder, and any other federal,
state, county or local statute, law, rule, regulation or ordinance relating to
public health, safety or the discharge, emission, or disposal to air, water,
land or groundwater, to the withdrawal or use of groundwater, to the use,
handling or disposal of polychlorinated biphenyls (PCB's), asbestos or urea
formaldehyde, to the treatment, storage, disposal or management of regulated
substances (including without limitation, petroleum, its derivatives, by-
products or other hydrocarbons), to exposure to toxic, hazardous, or other
controlled, prohibited or other regulated substances, to the transportation,
storage, disposal, management or release of gaseous or liquid substances, and
any regulation, order, injunction, judgment, declaration, notice or demand
issued thereunder.

       (b)  "Regulated Substances" means any substances, materials, wastes or
pollutants that are from time to time defined by or pursuant to or are
regulated as such under any statute, law, ordinance, rule or regulation of any
federal, state, regional, county or local authority having jurisdiction over
the Premises or its use, including without limitation, petroleum, petroleum
derivatives or by-products, or other hydrocarbons or any material, substance,
pollutant or waste that is (a) defined as a hazardous substance under Section
311 of CWA, (b) defined as a hazardous waste under Section 1004 of RCRA, (c)
defined as a hazardous substance under Section 101 of CERCLA, or (d) otherwise
regulated in its transportation, storage, disposal, management or release by
any federal, state, county or local statute, law, rule, regulation or
ordinance.

       (c)  "Release" means releasing, spilling, leaking, pumping, pouring,
emitting, emptying, discharging, injecting, escaping, burying, leaching,
migrating, disposing or dumping (in the appropriate tense for the context
used).

       (d)  "Notice" shall mean any summons, citation, directive, order,
claim, litigation, investigation, proceeding, judgment, letter or other
communication, written or oral, actual or threatened, from the Tennessee
Department of Environment and Conservation ("TDEC"), the United States
Environmental Protection Agency ("EPA") or other federal, state or local
agency or authority, or any other entity or any individual, concerning any
intentional or unintentional act or omission that has resulted or that may
result in the release of regulated substances into the waters (including
groundwaters) or onto the lands of the State of Tennessee or adjacent
jurisdiction, or into the "environment" as such term is defined in CERCLA from
or on the Premises, and may include, without limitation (i) the imposition of
any lien on the Premises, pursuant to any Environmental Laws (as defined
above) (ii) any violation of federal, state, regional, county or local
environmental laws, statutes, rules, regulations, ordinances, governmental
actions, orders or permits, or (iii) any knowledge, after due inquiry and
investigation, of any facts that could give rise to any of the above.

                            SECTION 14
                MECHANICS' AND MATERIALMEN'S LIENS

     Tenant shall not do or suffer anything to be done whereby the premises
shall be encumbered by a lien, and shall, whenever and as often as any lien is
filed against the premises purporting to be for labor or material furnished or
to be furnished to the Tenant, discharge the same of record within twenty (20)
<PAGE>
days after the date of filing.  Tenant shall indemnify Owner from all actions
and costs of suit by any person to enforce a lien, together with any costs and
attorney fees incurred by Owner.  Tenant may contest the validity of any lien
or claim if Tenant shall have posted a bond with adequate surety to insure
that immediately upon final determination of validity of the lien or claim
Owner shall be paid for any judgment rendered, with all proper costs and
charges, and Tenant shall at such time have the lien released without cost to
Owner.  Notice is hereby given that Owner shall not be liable for any labor or
materials furnished or to be furnished to the Tenant on credit, and that no
mechanics', materialmen's or other lien for any such labor or material shall
attach to or affect the reversionary or other estate or interest of Owner in
and to the real estate and improvements which are a part of the premises.

                              SECTION 15
                            ENTRY BY OWNER

     Tenant shall permit Owner, or Owner's agents or employees, at all
reasonable hours, to enter and examine the premises, or to show the premises
to persons wishing to rent or purchase the same, or to make proper repairs or
alterations, taking any space needed; and during the two (2) months preceding
the termination of any term of this lease, Tenant will permit customary "For
Sale" or "For Rent" notices, or both, to be exhibited on the premises.

                             SECTION 16
                               DEFAULT

     16.1     Should Tenant be in default in the payment of rent and remain in
default for a period of ten (10) days, such default shall, at Owner's option,
constitute a forfeiture of the lease.

     16.2     Should Tenant violate any other term, condition, or covenant of
this lease and not cease or otherwise cure the violation within thirty (30)
days after receiving written notice from Owner, or if Tenant should abandon or
vacate the premises prior to the expiration of the original or any extended
term of this lease, or if Tenant should be adjudicated a bankrupt or insolvent
according to law, or should make an assignment for the benefit of creditors,
or if a receiver, trustee or liquidator of Tenant's property shall be
appointed and not discharged within sixty (60) days, then the occurrence of
such act or omission shall, at Owner's option, constitute a forfeiture of the
lease.

     16.3  If a forfeiture is declared by Owner for any reason, then in
addition to and not in substitution for any responsibilities or liabilities of
Tenant, or any options available to Owner, under this instrument or applicable
law:

          (a)    Tenant shall be liable for all future rentals, any rents in
arrears and all other amounts necessary to compensate Owner for Tenant's
breaches of covenant, all such amounts to become immediately due and payable;
and

          (b)     Owner may, at Owner's option:  (i) lease the premises to
another tenant for part or all of the remainder of the term, in which event
there shall be set off against the amounts otherwise owed by Tenant the amount
of rents actually received from the new tenant less the costs related to
entering into the new lease and preparing the premises for the use of the new
tenant; or (ii) refrain from leasing the premises to another tenant, in which
event there shall be set off against the amounts owed by Tenant any portion of
the loss of net rental income available to Owner as to which Tenant may
<PAGE>
<PAGE>
establish, in a court of competent jurisdiction or to the satisfaction of
Owner, that Owner could have realized by leasing the premises to another
tenant known to Owner, or to another tenant with which Owner may have been
able to contract if Owner had expended reasonable efforts to locate such a
tenant.

     16.4     If, upon any forfeiture, Owner shall elect to recover possession
of the premises, no demand shall be necessary before such recovery of
possession; and Owner may enter the premises, or any part, and take possession
and expel Tenant or other occupants and their effects, without being guilty of
any trespass.

     16.5     Should Owner or Tenant fail to pay taxes or make repairs or fail
to perform any other duty under this lease the other party may, after giving
thirty (30) days' notice in writing, perform such duty and the cost of
performance shall be offset against or added to the rental amount and in the
latter case shall become immediately due and owing.

     16.6     The failure of Owner to declare a breach or forfeiture of this
lease for the violation of any term, condition or covenant shall not be
construed as a waiver of the rights to declare a breach or forfeiture of this
lease upon the occurrence of any subsequent act or omission, the right to
declare a breach or forfeiture being a continuing one in Owner.  Acceptance of
rentals subsequent to any forfeiture shall not be considered a confirmation or
renewal of this lease.

     16.7     Should Tenant vacate the premises prior to the expiration of the
original or any extended term of this lease, no act or actions taken by the
Owner or its agents shall be deemed an acceptance of a surrender of the
premises.  No agreement to accept the surrender of the premises shall be valid
unless the same be in writing and signed by the Owner.

                                 SECTION 17
                                SUBORDINATION

     This lease and all rights of Tenant hereunder are and shall be subject
and subordinate to the lien or liens of any and all mortgages, deeds of trust,
deeds to secure debt or other instruments in the nature thereof ("Owner's
mortgage"), and to all modifications, renewals or extensions thereof, which
may now or hereafter effect or encumber Owner's title to the premises.  Tenant
shall, upon demand, at any time or times, execute, acknowledge, and deliver to
Owner or to a holder of Owner's mortgage, without expense, any instruments
that may be necessary to make this lease subordinate to the lien of Owner's
mortgage.

                                 SECTION 18
                         OCCUPATION AFTER TERMINATION

     Should Tenant continue in possession, with or without the consent of
Owner, after expiration of the term or after a forfeiture incurred, Tenant
shall continue paying the amount of rent specified in this lease and shall
continue to be subject to all of the terms and conditions of this lease,
except that Tenant shall be the tenant at will of Owner, and in no event a
tenant from year to year or from month to month, and Tenant may be required to
vacate the premises without notice and may be removed by legal process as upon
a forcible and unlawful detainer.


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                                 SECTION 19
                                ATTORNEY'S FEE

     If it shall become necessary for Owner or Tenant to employ an attorney to
assert any right or enforce any obligation under this lease, after default,
such party, if he prevails, shall be entitled to recover, in addition to all
other costs and expenses, the reasonable costs and charges of such attorney.

                                 SECTION 20
                                   NOTICES

     All notices or communications which this instrument requires or permits
to be given shall be in writing and shall be mailed or delivered to the
respective addresses set forth below, or to such other address as may be
designated in writing by either party.

          To Owner as follows:

          Henry Luken
          900 Fairway Lane
          Soddy Daisy, TN 37379-4520

          To Tenant as follows:

          Covista, Inc.
          4801 Highway 58
          Chattanooga, TN 37416

                               SECTION 21
                            ENTIRE CONTRACT

     This lease contains the entire contract between the parties relating to
the demise of the premises and may not be altered, amended or changed except
by instrument in writing signed by both parties hereto.

                              SECTION 22
                           BENEFIT OF LEASE

     This lease shall inure to the benefit of and shall be binding upon the
heirs, legatees, legal representatives, and successors and assigns of the
parties, subject to all the terms, conditions and contingencies set forth.

                              SECTION 23
                             LAW APPLICABLE

     This is a lease under the laws of the state in which the premises are
located, and the validity and applicability of its provisions shall be
governed by the laws of that state.

                              SECTION 24
                    AMERICANS WITH DISABILITY ACT

     Tenant represents and covenants that it shall conduct its occupancy and
use of the Premises in accordance with the Americans with Disabilities Act
("ADA"), or any other federal, state or local law or regulation pertaining to
public accommodation access (including, but not limited to, modifying its
policies, practices and procedures, and providing auxiliary aids and services
to disabled persons at Tenant's expense).  Tenant agrees to indemnify and hold
<PAGE>
Owner harmless from all liability, damages, penalties, costs and attorney fees
arising from any claims brought or made against Owner resulting from Tenant's
use, operation or occupancy of the premises brought pursuant to the ADA or any
other federal, state or local law or regulation pertaining to public
accommodation access.  If the Tenant is allowed to make alterations and
improvements to the Premises in conjunction with the Tenant taking occupancy
of the Premises, Tenant agrees that all such work shall comply with the ADA.
Furthermore, Tenant covenants and agrees that any and all future alterations
or improvements made by Tenant to the Premises shall comply with the ADA.  Any
improvements in the premises necessary for Tenant's reasonable accommodation
of its employees will be made at Tenant's expense.

                              SECTION 25
                         ESTOPPEL CERTIFICATE

     At any time and from time to time, Tenant, on or before the date
specified in a request theretofore made by Owner, shall execute, acknowledge
and deliver to Owner a certificate prepared by Owner at Owner's expense,
evidencing whether or not (a) this lease is in full force and effect, (b) this
lease has been amended in any way, (c) there are any existing defaults on the
part of Owner hereunder to the knowledge of Tenant and specifying the nature
of such default, if any, and (d) the date to which rent, and other amounts due
hereunder, if any, have been paid.  Each certificate delivered pursuant to
this Section 25 may be relied on by any prospective purchaser or transferee of
Owner's interest hereunder or of any part of Owner's property or by any holder
or prospective holder of Owner's mortgage, or a mortgage or prospective
mortgage of any part of Owner's other property.

                              SECTION 26
                       TERMINOLOGY AND CAPTIONS

     The terms "Owner" and "Tenant" as used in this lease shall be construed
to apply to the parties in the appropriate gender and number; and the term
"Owner" shall in no way indicate that a tenancy greater than that described in
this lease is either demised or warranted.  The captions in this lease are
inserted only as a matter of convenience and for reference and in no way
define, limit, amplify or describe the scope of this lease or the intent of
any provision thereof.

     IN WITNESS WHEREOF, the Owner and Tenant have executed duplicate copies
of this lease this 1st day of September, 2001.


Copy No. ___
                                     /s/ Henry G. Luken, III
                                     --------------------------------
                                        (Henry G. Luken, III)

                                                                      OWNER

                                           COVISTA, INC.


                                    By: /s/ Thomas P. Gunning
                                       ------------------------------
                                          President

                                                                       TENANT

<PAGE>
<PAGE>
STATE OF TENNESSEE          )
                            )
COUNTY OF HAMILTON          )

     Before me, a Notary Public, duly appointed, commissioned and qualified in
and for the State and County aforesaid, personally appeared Henry G. Luken,
III, the within named bargainor, with whom I am personally acquainted, and who
signed, sealed and delivered the foregoing instrument in my presence, and who,
upon oath, acknowledged that he executed the foregoing instrument for the
purposes therein contained as his free act and deed.

     IN WITNESS WHEREOF, I have hereunto set my hand and affixed my seal at my
office in said State and County, on this the 1st day of September, 2001.


                              _________________________________
                                        Notary Public

                                My commission expires: __________

STATE OF NEW JERSEY         )
                            )
COUNTY OF PASSAIC           )

     Before me, a Notary Public, duly appointed, commissioned and qualified in
and for the State and County aforesaid, personally appeared
________________________, with whom I am personally acquainted, and who, upon
oath, acknowledged himself to be the President of Covista, Inc., the within
named bargainor, a corporation, and that he, as such officer of said
corporation, being authorized so to do, executed the foregoing instrument for
the purposes therein contained, by signing the name of the corporation by
himself as President.

     IN WITNESS WHEREOF, I have hereunto set my hand and affixed my seal at my
office in said State and County, on this the 1st day of September, 2001.

                         _________________________________
                                   Notary Public

                           My commission expires:___________