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EXHIBIT 23.26

15.044 -2005

PURCHASE AGREEMENT

SOCIEDAD AGRÍCOLA SAN SEBASTIAN LIMITADA (UNDER PARTITION)

AND

MINERA LUMINA COPPER CHILE S.A.

In Santiago, on this 18 day of October 2005, before me, Eduardo
Avello Concha, Notary of the 27th Notary of Santiago with offices at
Orrego Lucco 0153, Borough of Providence, hereby appear: on the one hand, Mr.
Rafael Vergara Irarrázabal, Chilean, married, engineer, ID No. 4.606.458 -5,
domiciled at San Damian 255, Las Condes, Santiago; and Mr. José Antonio Vergara
Irarrázabal, Chilean, married, lawyer, ID No. 6.062.332 -5, domiciled at Glamis
3241, department 801, Las Condes, Santiago, both by themselves and on behalf of
Sociedad Agrícola San Sebastián Limitada, farming company currently under
partition, Tax Payer Number 79.629.080 -3, domiciled at Asturias 97, Las Condes,
Santiago, hereinafter also referred to as the Seller; and, on the other
hand, Mr. John Joseph Selters, North American, single, mining engineering, ID
for foreigners No. 14.427.974 -3, on behalf, as shall be evidenced, of MINERA
LUMINA COPPER CHILE S.A., Tax Payer Number 99.531.960 -8, both domiciled for
purposes hereof at Las Nieves 3331, Vitacura, Santiago, hereinafter also
referred to as the Buyer and/orLumina; the appearing persons
being of the statutory age, who evidence their identities through the
aforementioned documents and hereby state:

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FIRST: Property.Seller is the only and
exclusive owner of the following assets:

a) Real Estate named Hijuela Carrizalillo Chico located in the
commune of Tierra Amarilla, Province of Copiapó, Third Region of Chile, which
include the areas of Potrero Chico, El Potrero Grande, El Florido, El
Tambo, La Higuera, Los Pozos, El Rincón and La Vega. The boundaries of
the referred Real Estate are: North, with Hacienda Jorquera; South, with
Hacienda Manflas; East, with Puntilla Negra de Quebrada Seca, which separate
it from Hijuela Quebrada Seca; and West, with Hijuela Los Hornos. Seller
acquired this Real Estate by purchase agreements subscribed indistinctly with
Mrs. Ninfa Orodina Aróstica Julio, Mrs. Wilna Teresa Aróstica Julio, Mrs. Milena
Liliana Aróstica Julio and Mr. Ovidio Caupolicán Aróstica Julio by means of
public deeds, all dated November 9, 1990, granted before the Public Notary of
Copiapó Mr. Jaime Morandé Miranda. The ownership title on behalf of Seller is
registered on page 7277, number 3431 and page 7291, number 3446 both of the
Property Registry of the Real Estate Custodian of Copiapó, corresponding to the
year 1990.

b) Consumable underground water rights, of permanent and
continuous exercise by a volume of 58,5 liters per second, that is pumped from a
well located within the Real Estate individualized in letter a) above. Seller
acquired this right by resolution number 537 of the Dirección General de Aguas
(DGA), dated December 17, 1993, which was reduced into public deed on February
14, 1994 before the Public Notary of Copiapó, Mr. Eduardo Cabrera Cortés. This
right is registered under the name of Seller at page 19, number 18, of the
Registry of Water Property of the Real Estate Custodian of Copiapó,
corresponding to the year 1994.

c) Consumable underground water rights, of permanent and
continuous exercise by a volume of 54 liters per second, that is pumped from a
well located within the Real

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Estate individualized in letter a) above. Seller acquired this
right by resolution number 244 of the DGA dated March 29, 1996, which was
reduced into public deed on May 20, 1996 before the Public Notary of Copiapó,
Mr. Eduardo Cabrera Cortés. This right is registered under the name of Seller at
page 37 overleaf, number 36, of the Registry of Water Property of the Real
Estate Custodian of Copiapó, corresponding to the year 1996.

d) Consumable underground water rights, of permanent and
continuous exercise by a volume of 40 liters per second, that is pumped from a
well located within the Real Estate individualized in letter a) above. Seller
acquired this right by resolution number 426 of the DGA dated June 28, 1996,
which was reduced into public deed on August 9, 1996 before the Public Notary of
Copiapó, Mr. Eduardo Cabrera Cortés. This right is registered under the name of
Seller at page 63, number 57, of the Registry of Water Property of the Real
Estate Custodian of Copiapó, corresponding to the year 1996.

e) Consumable underground water rights, of permanent and
continuous exercise by a volume of 60 liters per second, that is pumped from a
well named B located, according to the South American Provisory datum 1956, in
the UTM coordinates North: (m) 6.887.999 and East: (m) 410.957. Seller acquired
this right by resolution number 525 of the DGA dated July 25, 1996, which was
reduced into public deed on October 7, 1996 before the Public Notary of Copiapó,
Mr. Eduardo Cabrera Cortés. This right is registered under the name of Seller at
page 71 overleaf, number 64, of the Registry of Water Property of the Real
Estate Custodian of Copiapó, corresponding to the year 1996.

f) Consumable underground water rights, of permanent and
continuous exercise by a volume of 27 liters per second, that is pumped from a
well named C located, according to the South American Provisory datum 1956, in
the UTM coordinates

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North: (m) 6.889.172 and East: (m) 409.957. Seller acquired
this right by resolution number 586 of the DGA dated December 7, 1994, which was
reduced into public deed on January 31, 1995 before the Public Notary of
Copiapó, Mr. Eduardo Cabrera Cortés. This right is registered under the name of
Seller at page 5 overleaf, number 5, of the Registry of Water Property of the
Real Estate Custodian of Copiapó, corresponding to the year 1995.

g) Superficial water rights extracted from an artificial
flowing from the Copiapó River of consumable, permanent and alternative use,
which corresponds to 15 shares that are equivalent to two and a half hours of
watering with 1/5 of the river every 14 days, right riverside, Cordillera
Sector, coming from Carrizalillo Channel of the commune of Tierra Amarilla,
which tributary is Pulido River. The registration under Sociedad Agrícola San
Sebastián Limitada name was made, according to Water Code article 115, at page
95 overleaf, number 83 of the Registry of Water Property of the Real Estate
Registrar of Copiapó, corresponding to the year 1996; and certify number 36
dated June 1st, 2005, issued by Mr. Marco Larenas Contreras, Regional
Director of the DGA, Atacama Region. This right is established in the public
deed dated September 13, 1996, granted before the Public Notary of Copiapó, Mr.
Eduardo Cabrera Cortés, in which are enclosed the By-laws of the Copiapó River
and its Tributaries Vigilance Board and this right was acquired by means of the
public deeds referred to in previous letter a) of this clause. This right is
registered under the name of Seller at page 45, number 36, of the Registry of
Water Property of the Real Estate Custodian of Copiapó, corresponding to the
year 2005.

SECOND: Representations.Seller hereby
represents and warrants in favor of Buyer that:

a) It is the exclusive owner of the assets referred to in
clause first above and their titles are fully in force in accordance with
applicable law;

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b) The referred assets are free of liens, mortgages,
prohibitions, interdictions, seizures, promises, options, real or personal
rights, lease agreements on any other sort of agreement or instrument in favor
of third parties, and free of litigation or other restrictions that could affect
the transfer of the ownership and/or the use and enjoyment of the Property, and,
in general, free of all encumbrance, with the sole exception of the Real Estate
referred in letter a) of clause first above that has an electric line easement
created in favor of Sociedad Agrícola Iglesia Colorada Limitada, as evidenced in
registration made on page 238, No. 97 of the Mortgages and Encumbrances Registry
of the Real Estate Custodian of Copiapó, corresponding to the year 1987;

c) It does not require any consent or authorization from third
parties in order to execute the agreement herein;

d) There is no commenced legal action, litigation, complain or
procedure, nor it is aware of any of those that could be commenced, nor of facts
that could derive in the commencement of a legal action, litigation, complaint
or procedure, whether judicial or non judicial, in connection with the assets
referred to in clause first above, with the exception of the arbitral trial and
the partition trial that carry out Mr. Francisco Ruiz-Tagle Decombe between Luis
Rafael Vergara Irarrázabal and José Antonio Vergara Irarrázaval;

e) The assets have their legal titles in good standing
according to Chilean law;

f) It is not aware of third parties complains or of third
parties that could have rights over the assets and/or the fact that third
parties have applied for mining concessions over the surface covered by the Real
Estate referred to in clause first letter a) above;

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g) The payment of the Real Estates referred in clause first
letter a) above land tax is updated;

h) It has not executed any act breaching the legal and
regulatory provisions currently in force, specially the environmental provisions
contained in Act 19,300, and moreover, that all the activities executed within
the Real Estate referred in clause first above have fully comply with the
pertinent laws and regulation;

i) The Real Estate referred in clause first letter a) above is
free from occupants.

j) Mr. John Joseph Selters, on behalf of MINERA LUMINA COPPER
CHILE S.A., declares under oath that the latter is a Chilean company, with
domicile is located in Chile, that its capital have been entered by its Canadian
partners and that its control is held by North Americans that reside in Chile.
Mr. Rafael Vergara Irarrázabal and Mr. José Antonio Vergara Irarrázaval, by
themselves and as representatives and sole partners of SOCIEDAD AGR¥COLA SAN
SEBASTIÁN LIMITADA declare under oath that the seller company is Chilean.

THIRD: Purchase.Hereby and through
this instrument Seller, acting duly represented as mentioned herein, hereby
sells, assigns and transfers to Lumina, for whom its appearing representative
accepts and acquires, the Real Estate and its water rights all individualized in
letters a), b), c), d), e) f) and g) of the clause first above, as well as all
the rights derived therefrom in accordance with the law, belonging to Seller
pursuant to clause first above, notwithstanding the pending condition
established in clause seventh below and Buyers right to resolve this agreement,
loosing as damage indemnity all what was paid until that date, not having Seller
right to any other indemnity.

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FOURTH: Price.The purchase price of
the Real Estate referred to in clause first letter a) above amounts to
US$1.400.000. - dollars of the United States of America (hereinafter dollars),
payable at any event and un-refundable. This price will be increased in another
US$1.400.000. - if the pending condition referred to in clause seventh below is
totally or partially fulfilled, unless Lumina exercise its right referred to in
clause 8.2 below. The purchase price of the underground water rights referred to
in clause first, letters b), c), d), e) and f) amounts to US$9.200.000. -
dollars, from which US$100.000. - dollars will be payable at any event and
un-refundable and that amount will correspond to 15 liter by second of the water
rights referred to in letter c) clause first above. The parties leave on record
that the total price of the water rights may suffer some modifications according
to the level of fulfillment of the pending condition referred to in clause
seventh hereof. The purchase price of the superficial water right referred to in
clause first letter g) above amounts to US$300.000. - dollars.

Despite to what is mentioned in clause seventh hereof, the
parties have assigned the following prices for each one of the underground water
rights referred to in clause first letters b), c), d), e) and f) above:

a) The amount of US$2.247.182. - dollars that corresponds to
the price of the underground water right mentioned in clause first, letter b),
above.

b) The amount of US$2.074.321. - dollars that corresponds to
the price of the underground water right mentioned in clause first, letter c),
above.

c) The amount of US$1.536.534. - dollars that corresponds to
the price of the underground water right mentioned in clause first, letter d),
above.

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d) The amount of US$2.304.802. - dollars that corresponds to
the price of the underground water right mentioned in clause first, letter e),
above.

e) The amount of US$1.037.161. - dollars that corresponds to
the price of the underground water right mentioned in clause first, letter f),
above.

FIFTH: Price Payment.The prices
mentioned in the former clause, with the exception of the amount payable at any
event of 1.500.000 dollars referred to in letter a) below, and that in total
amounts to US$12.300.000. - dollars, notwithstanding the fulfillment of the
pending condition mentioned in clause seventh hereof, will be paid by Buyer to
Seller as follow:

a) With the amount of US$1.500.000. - dollars that Buyer pays
in cash in this act to Seller, stating the latter that he receives this amount,
completely and to its whole and total satisfaction, by submitting Buyer two 30
day bank deposits, one for 1.200.000 and the other for 300.000 dollars plus the
interest agreed herein that amounts to 9.290 dollars, renewable and endorsed to
Mr. Rafael Vergara Irarrázabal and José Antonio Vergara Irarrázaval to the
Notary that authorizes this deed, with the instruction to deliver them to Seller
once the assets subject to this contract are registered under Buyers name
before the pertinent Custodians. Buyer has to request these registrations within
the term of 10 days counted from the date hereof. For all legal effects, this
payment will be imputed to pay the price of the Real Estate, without its waters,
individualized in letter a) of clause first above and the equivalent to 15
liters from the underground water right individualized in clause first letter c)
above.

b) With the amount of US$4.300.000. - dollars or its equivalent
to Chilean pesos depending on the decision of Seller that must be taken within
the term of 48 hours counted from the reception of the letter mentioned in
clause sixth below and

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converted according exchange rate set forth in clause 14.7
hereof, sum that will be paid in or before the term of 365 days, counted from
the date of this agreement and that Buyer will pay to Seller in the way stated
in clause sixth below. For all legal effects, this payment will be imputed first
to pay the increased price referred to in clause fourth above of the total price
of the Real Estate individualized in letter a) of clause first above whether
there is an adjustment of the price according to clause seventh below and the
remaining will be imputed to pay the price of the water rights individualized in
clause first above, according to the terms and opportunities mentioned in clause
seventh hereof.

c) With the amount of $3.300.000. - dollars or its equivalent
to Chilean pesos depending on the decision of Seller that must be taken within
the term of 48 hours counted from the reception of the letter mentioned in
clause sixth below and converted according exchange rate set forth in clause
14.7 hereof, sum that will be paid in or before the term of 720 days, counted
from the date of this agreement and that Buyer will pay to Seller in the way
stated in clause sixth below, according to the terms and opportunities mentioned
in clause seventh hereof.

d) With the amount equivalent to Chilean pesos of $3.200.000. -
dollars or its equivalent to Chilean pesos depending on the decision of Seller
that must be taken within the term of 48 hours counted from the reception of the
letter mentioned in clause sixth below and converted according exchange rate set
forth in clause 14.7 hereof, sum that will be paid in or before the term of 1080
days, counted from the date of this agreement and that Buyer will pay to Seller
in the way stated in clause sixth below, according to the terms and
opportunities mentioned in clause seventh hereof.

The balance of the price indicated in the previous letters b),
c) and d) that will be owed according to clause seventh hereof, will accrue an
interest rate of Libor 360 days, plus 2,9 point (290 basic points), able to be
capitalized every 360 days, interest

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that will be paid jointly with each one of the installments of
the price indicated previously and calculated on the balance of price to that
date. The applicable Libor rate for the payment of the installment indicated in
letter b) above will be the effective one at the date of this contract plus its
surcharge; the Libor rate applicable for the payment of the installment
indicated in letter c) above will be firstly the Libor rate effective at the
date of this contract, plus its surcharge and then the Libor rate effective in
360 days counted from the date of this contract, plus its surcharge; the Libor
rate applicable for the payment of the installment indicated in letter d) above
will be the same rates applicable to the installments indicated in letter c)
above and then the Libor rate effective in 720 days counted from the date of
this contract, plus its surcharge.

The parties agree also that the prices established for the
water rights object of this purchase, excluding the interest agreed in this
clause, will be increased up to the amount corresponding to 50% of the first
category income tax that will be yield while the pending condition referred to
in clause fourth hereof is fulfilled. The referred increases that are part of
the prices and that today represent 17% of each payment, will be paid by Buyer
jointly with the payment of each installment in 50% by Buyer within the first 15
day of April of the year that is due to pay the tax (hereinafter Gross-Up
which will be calculated as follow: base price divided by one minus 50% of the
applicable tax rate, i.e. 100.000 at the 17% tax rate will be calculated as
follow (100.000) divided by 1 minus point 17 by point 50, from which the result
is 109.290 dollars).

In the case the 17% first category tax rate is modified, Buyer
will pay the referred 50% according to the new tax rate that may be in force at
the time the tax I paid.

SIXTH: Form of Payment.

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For purposes of foregoing clause five, Lumina shall notify
Seller, with at least 5 days of anticipation, the date on which each of the
indicated installments shall be paid, dates that cannot exceed the dated fixed
therein for each of the installments.

Such payment shall always be executed before the Public Notary
authorizing this agreement, or its successor or assignee, and against the
corresponding receipt public deed duly signed by the parties.

In case Seller, for any reason, does not receive the payment
and does not sign the corresponding receipt deed, then it shall be valid the
payment to be done by Lumina delivering to the Public Notary authorizing this
agreement, or its successor or assignee, a 30 days renewable bank deposit,
endorsed to Rafael Vergara Irarrázabal and José Antonio Vergara Irarrázaval,
with the instructions of handle the document to them against their signature of
the pertinent receipt deed.

SEVENTH: Pending Condition.The parties
agree that full payment of each one of the indicated price installments referred
to in letters b), c) and d) of clause fifth above will be subject to the pending
condition, able to be fulfilled at Lumina plenty satisfaction, consisting that
once Buyer has done a hydro-geologic model of Pulido River, considering at least
the area of the Real Estate, including among other electromagnetic studies and
all the works that Lumina considered necessary to extract the volume
corresponding to the rights of underground water individualized in the clause
first herein, as the rehabilitation of the existing wells and/or the relocation
and/or the drill of new wells, they will have to be able to yield jointly and
simultaneously, in a sustained and coordinated way a volume of at least 239.5
liters per second. However, the parties agree that if for any reason at the
expiry of any installment referred to in previous clause fifth, letters b), c)
and d), the yield tests have not been done or terminated, the respective price
quota will be

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paid totally and the pending condition will be applied only for
the remaining price quotas.

In the case, Lumina decides to relocate the wells in areas
outside of the Real Estate, the relocated litters per second will be considered
as effectively yield for the purposes of this pending condition.

Any join and sustain yield test of the five wells that Lumina
will do or has already done before any rehabilitation work, will establish the
minimum yield of them.

In case the volume possible to be yielded is smaller than 239,5
liters by second once the studies and works already described have been done,
the pending condition will be had as unfulfilled; in such case Buyer will be
able to resolve this agreement without right to ask reimbursements of the
already paid quotas, amounts that will be kept by Seller as damage indemnity for
emerging damages, not having the latter right to ask any other damage; or Buyer
will be able to ask the amendment of the amount of the installment that
correspond to pay, in proportion to the volume that indeed can be yield in a
continuous, joint and sustain way either from the current wells or from the new
system of wells.

If at the time of being made the wells yield measurement, they
yield more than 239.5 liters by second, Buyer will not have to pay more than the
agreed installment.

The parties agree that any work that will de done to the
current wells, must be done in a way to avoid any damage. If Buyer decides to
resolve this contract, the latter will have to return the wells in perfect
conditions, in the same condition and status he receives the wells, having in
consideration its legitimate use of them.

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Once Lumina has paid the installment indicated in letter d) of
the clause fifth herein, and if it has exerted its right to request for the
proportional amendment of the price for the partially un-fulfillment of the
pending condition, which means Buyer intention not to retain all the water
rights corresponding to 239,5 liters per second, Lumina will transfer to Seller
in a price of US$1,00 dollar each liters by second that actually cannot be
extracted and that consequently the parties will have amended from the price.
The fact that Lumina may transfer water rights to Seller, will not give the
latter the right to pump or to use the wells that Lumina would use and in this
regard Seller, using its retransferred water rights, will never affect the
volume of Lumina water rights, subject of this contract. For the latter, Seller
previously to drill or to build any well(s) to yield the retransferred water
rights, must be sure that those well(s) are located outside the protection area
set by the expert arbitrator mentioned bellow, in order to avoid any damage to
Luminas water rights. Lumina obliges itself to grant inside its property the
easements and/or rights of way that will be necessary for Seller to have access
to, to build and to operate the well(s) from where the re-transferred water
rights will be yielded.

In this act, the parties decide that the works destined to the
rehabilitation of current wells and the relocation or perforation of new wells,
as well as the measurement of their real yield, will be made by a specialized
company chosen and paid by Buyer. Seller is entitled to have access to the
information from the studies, works and project is the latter cause no problem.
For that reason Seller will appoint at its own cost a technical expert. Buyer
will submit to Seller all the necessary information obtained from the studies
and works, so the parties together will be able to agree whether the condition
is fulfilled or not. If trying to determine the verification of the pending
condition, the parties do not agree in the real yield of the wells, having
previously Buyer submit the work and studies information to Seller, the parties
will take the case to an expert arbitrator whom the parties will jointly
designate and its decision will be biding and final for the parties. If they do
not agree who the arbitrator should be, the

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latter will by appointed by the President of the Chilean
Society of Hydraulic Engineers.

EIGHTH: Delay and Lack of
Payment.8.1In case Buyer delays the payment of any installment
set forth in clause five above, Seller shall provide written notice to Buyer who
in turn shall have the term of 15 business days to complete such payment plus a
penal interest equivalent to the maximum daily conventional interest in effect
in Chile for operation in foreign money.

8.2If the term mentioned in the former paragraph is
elapsed and Buyer does not pay any of the installments set forth in clause five
above, or if Buyer, at any time shows his willingness to stop paying such
installments, Seller shall only be authorized to claim partially the resolution
of this agreement, and, additionally, shall have the right to keep, as a unique
indemnification, every amount received prior to such claim. For purposes hereof,
the parties hereby agree that all the damages that Seller may suffer due to the
lack of payment of one or more installments described in clause five above and
due to the partial resolution of this purchase, whatever the nature, class or
amount of the damages Sellers may have, shall be always equivalent to the
currency quantities previously received by Seller as part of the price. The
parties hereby mutually and conventionally appraise said damages upon such
currency quantities effectively received by Seller from Buyer.

Seller will have the right to claim the partial resolution of
this agreement since it will not be able to request the resolution of the
contract in which it refers to the Real Estate and underground water rights
equivalent to 15 liters per second from the water right referred to in previous
letter c) of clause first, whose prices are understood cancelled by the payment
indicated in letter a) of the clause fifth herein.

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In that case, Seller will be able to freely and unrestrictedly
dispose all the water rights with the exception of the 15 liters per second
mentioned above.

NINETH: Actions Waiver.9.1. For all
pertinent legal effects, Seller hereby expressly waives the action to claim the
enforcement of this agreement, therefore, any Buyers infringement in regards to
the timely payment or lack of payment of the price installments provided in
clause five above, shall only entitle Seller to partially claim this agreements
resolution with the exception of a portion of the Real Estate and the
underground water rights equivalent to 15 liters extracted from the water right
mentioned in precious letter C9 of clause first, which prices were paid by means
of the letter a) of the clause fifth above.

9.2. For all the effects to determine what portion of the Real
Estate will correspond to the lots that Buyer will retain at any event, the
Parties hereby indicate that this surface will correspond to the areas of the
Real Estate that are not necessary for the operation and location of the wells
from which the volume corresponding to the water rights individualized in clause
first letters b), c), d), e) and f) above is extracted. For these effects, Buyer
will have to prepare a division project of the Real Estate individualized in
clause first letter a) above, within a term of 360 days counted from this
agreement, identifying those sectors that are necessary for the operation of the
referred wells and those sectors that are not, so these sector will be used by
third parties in agricultural and forestry activities. The referred division
project would be modified by Lumina if, for the better use of the water rights
object of this contract, is technically necessary.

Seller hereby expressly waives to any action to claim damages
different from those set forth in clause eighth herein.

TENTH: Purchases Form.

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The purchase is done ad corpus, in the state in which
the Real Estate and water rights currently are, including all what is built,
forested and seeded, and, in general, with all things reckoned as immovable due
to adherence or destination, uses, customs and easements, whether active or
passive, free of occupants and from any type of mortgages, liens, seizures,
debts, litigation and prohibitions, whether currently known by the parties or
not, different from the easement mentioned in clause second, letter b)
above.

ELEVENTH: Clearance.Seller shall be
liable for clearing vices in accordance to Chilean law.

TWELFTH: Material Delivery.The
material delivery of the Real Estate and the water rights is hereby made.

THIRTEENTH: Arbitration.Any difficulty
or controversy that may arise between the contracting parties regarding the
application, interpretation, duration, validity or execution of this agreement
or any other controversy regarding it, will be subject to arbitration, with the
sole exception specific matter related to the real volume that can extracted
from the referred wells, matter that will be subject to the technical
arbitration referred to in previous clause seventh. This arbitration will be in
accordance with the current Arbitration Procedural Regulations of the
Arbitration and Mediation Center of Santiago. The parties grant irrevocable
special power to Santiago's Chamber of Commerce, so that, upon written request
from any of them, designate an arbitrating arbitrator from the members of the
arbitration body of Arbitration and Mediation Center of Santiago, submitting it
in this case to the procedure established by the Regulation of said Center,
which evidenced through public deed dated December 10, 1992, executed in the
Public Notary for Santiago of Mr. Sergio Rodríguez Garcés and to its subsequent
amendments, that the parties declare to know and accept. Against the
arbitrator's resolutions no appeals will

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be filed, for which reason the parties expressly waive them,
including those of complaint and cassation.

The arbitrator is specially empowered to settle any matter
related with his competence and/or jurisdiction.

FOURTEENTH: Miscellaneous.14.1
Confidentiality. Any information or data obtained in connection with the
performance of this agreement is confidential for Seller who shall not make any
public statement concerning this agreement or the activities contemplated
thereunder without the prior written consent of Buyer, which consent shall not
be denied without justified reason.

14.2 Notices. All notices to be made or given by a party
hereunder shall be in writing and delivered by mail or by facsimile to:

To Seller a) Don Rafael Vergara IrarrázabalCalle San
Damián N° 255, Las Condes, Santiago, Chile. Fax: 56-2-217 27 83 b) Don
José Antonio Vergara IrarrázavalCalle Glamis N° 3241, Depto. 801, Comuna de
Las Condes, Santiago, Chile. Fax: 56-2-

To BuyerMinera Lumina Copper Chile S.A. Las Nieves
3331, Vitacura Santiago Att.: John Joseph Selters

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Fax: (56-2) 325-7572

A party may change its address by notice to the other
party.

All notices shall be given:

a) by personal delivery (including courier), which shall be
deemed to have been delivered on the day on which it shall have been delivered
to an adult located in the aforementioned domiciles.

b) by registered mail, charges prepaid.

c) by electronic communication, which shall be deemed to have
been delivered upon the production by the dispatching facsimile machine of a
transmission report showing the relevant number of pages comprising the relevant
document to have been sent to the correct facsimile number and the result of the
transmission as OK (or equivalent expression) unless the recipient notifies
the sender within twenty-four (24) hours that the transmission was not legibly
received.

All notices shall be effective and shall be deemed
received:

a) if by personal delivery or by registered mail, on the date
of delivery if delivered during normal business hours, and if not delivered
during normal business hours, on the next business day following delivery;
or

b) if by electronic communication, on the next business day
following receipt of the electronic communication.

Saturday will not be considered a business day for all effects
of this clause 14.2.

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14.3 Binding agreement and assignment. This agreement is
binding and compulsory upon the parties and will operate in their benefit
thereof. Seller shall not assign all or any part of this agreement, including
the credit guaranteed by the mortgage referred to in clause fifteenth below,
with the exception of the transference made to any company under the direct and
final control of Rafael Vergara Irarrázabal and/or José Antonio Vergara
Irarrázaval, or, to a related company, but this with previous written consent of
Buyer, which will not be held without cause and in both cases will be notified
to Buyer the name of the assignee.

14.4 Applicable Law. This agreement is executed and
governed by the laws of the Republic of Chile.

14.5 Domicile. For all purposes hereof, the parties
hereto set their domicile in the city of Santiago.

14.6 No Third Party Beneficiary Rights. This agreement
is for the benefit of the parties and their respective successors and assignees
only, and is not intended to create third party beneficiary rights in any other
party or in any government, governmental organization or agency.

14.7. Money Exchange.If Seller chooses to receive
payment in Chilean pesos, the sum of money corresponding to those payments
herein expressed in dollars of the United States of America will be paid in
Chilean pesos, in accordance with the exchange rate for the Observed dollar,
as published by the Central Bank of Chile in the Official Gazette on the day
prior to the corresponding payment. In the absence of said exchange rate, the
exchange rate Law No. 18.010, article 20, first paragraph, on Money Credit
Operations, will apply.

FIFTEENTH: Mortgage.

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In order to guarantee the balance of the price set forth in
clause five letter b), c) and d) herein, Buyer hereby constitutes in favor of
Seller a mortgage over the underground water rights referred to in clause first,
letters b), c), d), e), and f), which must be recorded at the margin of the Real
Estate ownership registration of the referred underground water rights to be
done under Buyers name in accordance to this agreement.

SIXTEENTH: Expenses.Any notary fees
arising from this deed will be equitably borne by the parties hereto. Expenses
arising from the payment of any fees at Real Estate Registrars Office will be
exclusively borne by Buyer.

SEVENTEENTH: Prohibition to change use of
soilHereby, the parties declare that the Real Estate object of this
agreement is affected by a prohibition to change the use of the soil established
in articles 155 and 156 of the General Law of Urbanism and Constructions.

Power of Attorney.The bearer of an authorized copy
hereof is empowered to request any appropriate registrations, sub-registrations,
cancellations and annotations at the competent Real Estate Custodians
Office.

In addition, the parties hereto empower any one of Messrs.
Carlos Pérez-Cotapos Subercaseaux, Gonzalo Grez Jordán, Carlos Prat Guarachi and
Rodrigo Fernández Robinson, so that any one of them may execute rectifying or
clarifying deeds as necessary for the correct individualization and registration
of the Property under Buyers name, and to carry out any necessary acts or
registrations arising herefrom, notwithstanding any quoting mistake related to
registrations of same Registrar, or any error in identifying the Property that
is object of this purchase agreement, that the

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parties may have made, exclusively considering that the will of
the parties hereto is that as expressed in the different clauses and
stipulations herein contained.

LEGAL CAPACITIES.The legal capacity of John Joseph
Selters to act on behalf of MINERA LUMINA COPPER CHILE S.A. is stated on the
public deed dated September 5, 2003 subscribed before the Public Notary of
Santiago Mr. Eduardo Avello Concha.

The legal capacity of Rafael Vergara Irarrázabal and José
  Antonio Vergara Irarrázabal to act on behalf of SOCIEDAD AGRÍCOLA
  SAN SEBASTIÁN LIMITADA is stated on the public deeds dated February 24,
  1986 and August 30, 1991, both subscribed before the Public Notary of Santiago,
  Mr. Juan Ricardo San Martín Urrejola.



MINERA LUMINA COPPER CHILE S.A.



SOCIEDAD AGRÍCOLA SAN SEBASTIÁN LIMITADA

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