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                                                                    EXHIBIT 4.11

                       MINING OPTION TO PURCHASE CONTRACT

                                 BY AND BETWEEN

                    SOCIEDAD CONTRACTUAL MINERA LOS POTRILLOS

                                       AND

                            METALLICA RESOURCES INC.

               (ENGLISH TRANSLATION OF SPANISH LANGUAGE DOCUMENT)

IN SANTIAGO, CHILE, ON SEPTEMBER 2, 2004 appear: RENE BENAVENTE CASH, Chilean,
attorney, Titular Notary Public of the 40th Notary of Santiago, at Huerfanos
979, 3rd floor, appear: OSVALDO CAUTIN MORUNA, Chilean, married, engineer,
Chilean national identity card number 5.364.859-2, appears on behalf of SOCIEDAD
CONTRACTUAL MINERA LOS POTRILLOS, Chilean tax identity number 76.145.660-1,
hereinafter indistinctly referred to as "LOS POTRILLOS" or "the Property Owner",
legal entity conducting its own business, both domiciled for these purposes at
Mac-Iver 459, Santiago, Chile; and PABLO MIR BALMACEDA, Chilean, married,
attorney, Chilean national identity card number 6.374.989-3, on behalf of MINERA
METALLICA LIMITADA., a company legally constituted in Chile pursuant to its
laws, Chilean tax identity number 78.840.880-3, hereinafter also and
indistinctly referred to as "METALLICA" or "the Beneficiary", both domiciled for
these purposes at Enrique Foster Sur 20, 9th floor, Las Condes, Santiago, Chile;
the appearing

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parties being of legal age and having evidenced their identities by producing
the aforementioned Chilean national identity cards and state:

1. MINING PROPERTY

Osvaldo Cautin Moruna states that the party which he is representing, LOS
POTRILLOS, is owner of the exploitation concessions that are indicated below,
hereinafter referred to as "Mining Property", which together form "Proyecto
Enrique-Joscelyn"; whose state is that which is indicated; all located in the
community of Tierra Amarilla, Copiapo, Region III of Atacama; and, whose titles
are registered in the Conservator of Mining, Copiapo, as indicated as follows:

ONE.- "ENRIQUE PRIMERO UNO AL DOCE";

TWO.- "ENRIQUE UNO TRECE AL CATORCE";

THREE.- "ENRIQUE UNO QUINCE AL DIECISEIS";

FOUR.- "ENRIQUE UNO DIECISIETE AL VEINTIUNO";

FIVE.- "ENRIQUE DOS UNO AL DOS";

SIX.- "ENRIQUE DOS TRES";

SEVEN.- "ENRIQUE DOS CUATRO AL SEIS";

EIGHT.- "ENRIQUE DOS NUEVE AL ONCE";

NINE.- "ENRIQUE SEGUNDO SIETE AL OCHO";

TEN.- "ENRIQUE SEGUNDO DOCE AL VEINTIUNO";

ELEVEN.- "ENRIQUE TRES UNO AL OCHO";

TWELVE.- "ENRIQUE TRES NUEVE AL CATORCE";

THIRTEEN.- "ENRIQUE TRES QUINCE AL TREINTA";

FOURTEEN.- "JOSCELYN PRIMERA UNO AL VEINTE";

FIFTEEN.- "JOSCELYN SEGUNDA UNO AL VEINTE";

SIXTEEN.- "JOSCELYN TERCERA UNO AL VEINTE";

SEVENTEEN.- "JOSCELYN CUARTA UNO AL VEINTE";

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EIGHTEEN.- "JOSCELYN QUINTA UNO AL TREINTA";

NINETEEN.- "POTRILLO DOS AL VEINTISIETE";

TWENTY.- "BELLAVISTA DOS AL VEINTIDOS".

The area corresponding to the stretch of land one (1) kilometer from the
perimeter of each one of the Mining Properties particularized in this clause
also forms part of the "Enrique-Joscelyn Project" and consequently of this
contract, the sum of the area corresponding to each one of the Mining Properties
is considered the "Area of Interest" which is described in the attached plan
which is signed by the parties and formalized at the end of this register and is
understood to form part of this contract for all legal purposes.

2. REPRESENTATIONS

The "Property Owner", represented by Osvaldo Cautin Moruna, represents and
warrants that it has exclusive and full ownership of the Mining Property; that
there are no overlapping third party rights that could allow a third party to
explore or exploit any grantable estate on the same land; the Mining Property
was acquired with fair title, in good faith and in accordance with applicable
laws and regulations; all transfers of ownership have made legally and no third
party can, on a sound basis, claim rights or challenge the validity of the
constitution of the rights; the Mining Property has been constituted in
accordance with the applicable laws, regulations and norms; the Mining Property
is free of all mortgages, encumbrances, prohibitions, promises or options of any
nature, impediments, litigation or other third party rights, including any
legal, judicial or voluntary rights that may affect, disturb or obstruct its
free disposition or transfer.

The aforementioned is notwithstanding the prohibitions and encumbrances that are
constituted herein.

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3. OPTION TO PURCHASE

LOS POTRILLOS, duly represented by Osvaldo Cautin Moruna, hereby grants the
right and option to purchase and is unilaterally obliged to sell, assign and
transfer to METALLICA, represented by Pablo Mir Balmaceda, the Mining Property
particularized in Clause 1 of this contract. For the purposes referred to, the
Property Owner, hereby, consents to the possible sale and purchase of the said
Mining Property. The Beneficiary, for its part, hereby represents that it has
received the offer of option to purchase and reserves the power to freely
exercise it within the term and upon the conditions stipulated in this contract.

The following are expressly understood as included within the object and price
of this option contract: any rights and administrative permits, including of
third parties associated with the ownership of the Mining Property
particularized in clause 1 that is currently owned by LOS POTRILLOS, such as all
easements of any nature, civil or mining, previously constituted or being in the
process of constitution, that may be necessary for the use, enjoyment and
benefit of the mining concessions particularized in the clause 1 or that access
such concessions. Furthermore, any renewals, extensions or replacements of the
concessions or mining rights particularized in clause 1 are understood to be
included in this option contract.

4. EXPLORATION EXPENSES, TERMS AND AMOUNTS TO INVEST.

To maintain this contract in force, METALLICA shall, during the period of 40
months from May 1, 2004, effect certain exploration expenses, hereinafter
referred to as "Exploration Expenses", in accordance with its experience and

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criteria, investing, within the terms that are indicated in each case, the
minimum amounts of money that are indicated as follows.

ONE.- METALLICA shall invest, within a period of no more than 16 months from May
1, 2004, the amount of money equivalent in Chilean national currency (pesos) to
US$375,000.- in accordance with the exchange rate and value referred to in
Clause 13 of this contract;

TWO.- METALLICA shall invest, within a period of no more than two years from the
date of this contract, the additional amount of money equivalent in Chilean
national currency (pesos) to US$500,000.- in accordance with the exchange rate
and value referred to in Clause 13 of this contract; and,

THREE.- METALLICA shall invest, within a period of no more than three years from
the date of this contract, the additional amount of money equivalent in Chilean
national currency (pesos) to US$725,000 in accordance with the exchange rate and
value referred to in Clause 13 of this contract.

The parties state that the sums of money invested in each period as Exploration
Expenses are accumulative, so that METALLICA shall invest the total sum of
US$1,500,000 in the period of 40 months from May 1, 2004, unless METALLICA
exercises the option to purchase in advance.

If METALLICA does not comply with the amount of investment in each of the terms
indicated above and the said fact is certified by a nationally and
internationally recognized and renowned independent auditor company, as accepted
by the parties, hereinafter referred to as "Independent Auditors", the parties
agree that METALLICA shall increase its investment in the following period by
the amount and difference indicated in the certificate issued by the

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Independent Auditors which, in any event, shall be verified within the period of
six months from the date of the commencement of the following period, without
representing, in any manner whatsoever, an increase of the term underway. If
METALLICA in any of the periods stipulated in this clause makes greater
investments than those which correspond to the said terms, it may attribute the
excess of the expenses effected to the following periods. Such greater
investments, if relevant, in any event may be attributed to the purchase price
offered.

In the event that the intervention of the Independent Auditors is necessary as
contemplated in this clause, whether for matters set forth above or as otherwise
contemplated in this contract, the parties agree that such cost will be borne by
the losing party, that is, the party who the Independent Auditors issues its
report against.

In any event, if METALLICA exercises the option to purchase in advance in
accordance with that stipulated in Clause 7, it shall not be obliged to make the
investments established in Clause 4. On the contrary, if METALLICA does not
exercise the option established in this contract, its waiver shall only have
effect if the investment indicated in number ONE.- of this clause is evidenced
before the Property Owner, otherwise, upon effecting the same act of waiver,
METALLICA shall pay LOS POTRILLOS the amount of money corresponding to the
difference between the expenses effectively paid and $US375,000 as it is obliged
to invest during the first period.

For the purposes of this clause, the parties understand the following by
Exploration Expenses: All expenses, direct and indirect, incurred by or on
behalf of METALLICA with respect to the operations, which shall include the
value of all time, money and equipment, furnished or used on or in relation to

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the Mining Property and/or the Area of Interest, by or on behalf of METALLICA,
including, but not limited to:

1) All time and expenses of contractors and consultants that work on the Mining
Property and/or the Area of Interest in the exploration operations, including
all time and expenses of geologists and other staff of METALLICA;

2) All costs of engineering, design, trials, obtaining permits, site preparation
and others, such as mapping, sampling, analysis costs, drilling, metallurgic
tests, engineering studies, materials and equipment rental;

3) All Mining Property maintenance costs, including, expenses incurred by
METALLICA and that are related to: (a) the defense and constitution of the
Mining Property; (b) the constitution of water rights; (c) the constitution of
easements or rights of way over the surface property; (d) land reparation
expenses (e) expenses of studies, reports and permits in order to fulfill
technical, environmental protection and/or mining safety regulations for the
exploration operations; and (f) all other geological, geophysical, geochemical,
metallurgic, hydrological; and other engineering works carried out for the
benefit of the Mining Property and/or the Area of Interest;

4) All costs of equipment, materials, combustibles, basic services and
suppliers, necessary for exploration operations; and,

5) All costs incurred in the preparation of feasibility and other studies
related to the exploration, if any.

5. PERIODIC REPORTS AND MEETINGS.

The parties agree that METALLICA shall issue half-yearly reports in Spanish
language in respect of the investment and expenses effected by it, reports that
in any case, shall contain the results obtained in each one of the
aforementioned periods. In the event that either party makes a request in
writing to the other, the parties shall meet to discuss any doubts in respect of
such report within the

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period of 30 days following the delivery by METALLICA to LOS POTRILLOS of the
respective report.

6. APPLICABLE LEGAL PROVISIONS.

The parties agree that this option contract shall be regulated by that set forth
in Article 169 of the Chilean Mining Code, in such a manner that METALLICA is
absolutely authorized to manifest or not its consent to accept the irrevocable
offer and, consequently, to perfect the sale and purchase contract.

7. TERM TO EXERCISE THE OPTION TO PURCHASE.

In the event that METALLICA elects to exercise the option to purchase the Mining
Property, it shall express the same by way of a public deed of acceptance
granted before the same Notary Public which authorizes this contract, or his
deputy or replacement, within the period of 5 years from the date of this
contract. In the event that METALLICA expresses its will to exercise the option
to purchase and in the event that all payments or any of the installments that
are established in Clause 10 are pending, at the time of entering into the deed
of acceptance, it shall deliver to the respective Notary Public a check, bank
bond or deposit of indefinite term, renewable and endorsable, taken in favor of
SOCIEDAD CONTRACTUAL MINERA LOS POTRILLOS, for the amount of money
representative of the price of the purchase option pending payment, as
stipulated in Clause 10 of this contract, with the instruction of delivering it
to the agent-in-fact of the Property Owner, upon production of a certificate
issued by the Conservator of Mining, Copiapo, evidencing that the Mining
Property indicated in Clause 1 is registered in favor of METALLICA and free of
all mortgages, encumbrances, prohibitions, interdictions and litigation. By the
sole fact of signing the public deed of acceptance referred to, the Beneficiary
shall have perfected the sale and

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purchase contract, provided that it is the agreement made by this option
contract and such deed of acceptance. The bearer of the authorized copies is
authorized to require the relevant registrations, sub-registrations and
annotations.

8. WAIVER

If the Beneficiary does not express its will to accept the sale and purchase
contract proposed, within the period of five years as stipulated in the previous
clause, or if by way of a public deed it expresses its will not to continue with
the option contract; or if it does not pay in a timely and integral manner one
or any of the installments of price as contemplated in Clause 10 as follows; or
if it does not effect the Exploration Expenses required in terms indicated in
Clause 4; or if it does not reimburse LOS POTRILLOS the value of the mining
patents paid by the Property Owner in terms of clause 2, the option to purchase
and the irrevocable offer shall remain, ipso facto, without effect and METALLICA
waives its right to be reimbursed for any amount of money that it has invested
or paid to LOS POTRILLOS as part of the price, the latter maintaining all sums
to its benefit as titleholder of all indemnification and any corresponding
advance loss. In this case, therefore, METALLICA shall not be obliged to pay LOS
POTRILLOS the amounts or installments which have not accrued, of the purchase
price offered as established in clause 10, and furthermore it shall not be
obliged to invest or pay the amounts promised for Exploration Expenses as
indicated in clause 4, with the sole exception being that indicated in number
ONE.- of that same clause. In this case, it shall immediately remove all
prohibitions and encumbrances that have been constituted by reason of this
contract, upon showing to the respective Mining Conservator the corresponding
public declarative deed; or a certificate of the Notary Public having granted
this deed, or its replacement or deputy, evidencing that the terms stipulated
have passed without the Beneficiary having accepted the offer and exercised the

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option, or without having paid one of any of the installments of the option as
agreed in Clause 10 as follows or all of them; or a certificate issued by the
Independent Auditors named by both parties, authorized by the same Notary Public
that grants this deed, or its replacement or deputy, evidencing that it has not
complied with the Exploration Expenses within the terms indicated, whether this
certificate is issued in respect of any of the three periods indicated in Clause
4 above, or all of them, in the terms previously indicated in the clause
referred to, considering, consequently, the authority that arises for METALLICA
to invest the amount pending in the event of a negative certification of the
investment of each period by the Independent Auditors, all in the form, amount
and term indicated in Clause 4. The Beneficiary confers a limited and
irrevocable power of attorney on LOS POTRILLOS, as broad as necessary, to reduce
to public deed the certificate that the Notary that grants this deed, or its
replacement or deputy, is authorized to issue to any titleholder or the
certificate that the Independent Auditors are authorized to issue, in accordance
with this clause, instruments that the parties, furthermore, consider sufficient
to enable the corresponding Conservator of Mines to release the encumbrances
constituted by this exploration contract with option to purchase, provided and
when METALLICA has not increased its investment in the following stage in
accordance with Clause 4. In the event that the parties do not agree upon the
naming of the Independent Auditors within the term of 30 days as set forth in
this deed, the party that has requested the nomination shall remain authorized
to make a valid nomination on its own behalf.

For the purposes of removing the encumbrances constituted by this contract,
METALLICA shall issue the deed of release within the period of 30 days from the
date of the cause of termination of this contract particularized in this clause.

9. EXPLORATION AND DEVELOPMENT EXPENSES.

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All expenses, direct and indirect, that are related to exploration, shall be
born, fully and exclusively, by METALLICA, and not attributable to the price of
the option, the Beneficiary being authorized to associate itself with third
parties or subcontract for the purposes of exploration development.

10. PURCHASE PRICE OFFER

The total purchase price offered in respect of the Mining Property object of
this contract is the amount of US$3,500,000, an amount that is payable and shall
be paid to SOCIEDAD CONTRACTUAL MINERA LOS POTRILLOS in accordance with the
following calendar:

ONE.- The sum of US$100,000 to be paid upon entering into this deed, in cash,
equivalent as of the date of this contract to $62.676.000 Chilean pesos, the
Property Owner stating that it has received the same to its complete
satisfaction;

TWO.- The sum of US$200,000 to be paid not later than one year from the date of
this contract.

THREE.- The sum of US$200,000 to be paid not later than two years from the date
of this contract.

FOUR.- The sum of US$400,000 to be paid not later than three years from the date
of this contract.

FIVE.- The sum of US$750,000 to be paid not later than four years from the date
of this contract.

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SIX.- The sum of US$1,850,000 to be paid at the time of exercising the option,
not later than five years from the date of this contract.

In the event that METALLICA elects not to exercise the option, subject matter of
this contract, however its negative will is expressed or implied, through one of
the forms indicated in Clause 8 above, or by any other unequivocal manner,
whatever amounts of money indicated in numbers ONE to FIVE above have been paid,
the amounts shall in no case be returned by the Property Owner. Equal treatment
shall be applied to the money invested in Exploration Expenses. Furthermore, in
such event all payment obligations of price and investment in Exploration
Expenses that this contract imposes upon METALLICA shall cease, with the sole
exception of the obligation to complete the investment in exploration as
referred to in number 1 of clause 4, if at the date that METALLICA expresses its
will of not exercising the option, whatever the form of the negative will that
is expressed or inferred, of any form whatsoever as indicated in clause 8 above,
or any other unequivocal form producing the same effect, this investment should
not have been completely carried out.

11. PAYMENT OF NET SMELTER RETURN ("NSR")

The parties agree that independent of the price stipulated in the previous
clause, once the option to purchase has been exercised and the Mining Property
has been acquired by METALLICA, it shall pay to LOS POTRILLOS, subject to the
terms and conditions that are indicated hereinafter, an amount equivalent to
1.5% of the Net Smelter Return ("NSR") for copper, gold, silver and molybdenum,
of those minerals extracted from the Mining Property referred to, upon the terms
and other conditions agreed in Annex A, a document that forms an integral part
of this contract and that is formalized under the same repertory number as this
deed on the same day in the Register of the Notary Public that authorizes this
deed. For the

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purposes of payment of this percentage of NSR as agreed, its value shall be
converted in dollars of the United States of America and payment shall be
verified in accordance with clause 14 as follows. Payment of this royalty shall
be made half-yearly within the period of 15 days following the expiry of the
period in which the same is accrued, with the exception of the first payment
which shall be made within 15 days following the expiry of 6 months after the
first anniversary of the Start-Up of the Project. For all purposes START-UP
shall mean that moment when the operational tests have been carried out in it or
the plants associated with it or the mines of the Mining Property, when the
first Mining concentrates or products as treated minerals and substances
extracted from the Mining Property are marketed, whether for sale in the
internal market or by way of exportation.

12. PURCHASE OF NET SMELTER RETURN ("NSR")

If LOS POTRILLOS decides to assign, sell or transfer the NSR stipulated in the
previous clause, METALLICA shall have the right, prior and preferable, to
acquire the said NSR, in accordance with the following rules:

a)    If LOS POTRILLOS receives a serious offer to purchase and decides to
      transfer its NSR, it shall promptly notify METALLICA of this fact, by way
      of a registered letter. This notification shall contain the price and
      other terms and conditions of the offer received. METALLICA shall have the
      period of 60 days from the date it receives the notification from LOS
      POTRILLOS to decide if it will acquire all the NSR at the same price and
      upon the same terms and conditions established in the offer received by
      LOS POTRILLOS. If METALLICA decides to acquire the NSR, the purchase shall
      be materialized within the period of 60 days from the date that METALLICA
      accepts to acquire the NSR.

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b)    If METALLICA decides not to acquire the NSR, does not accept the offer
      within the period stipulated, or does not materialize the acquisition
      within the maximum period established, LOS POTRILLOS within the period of
      60 days from the date of notification to the contrary, or if the requisite
      period expires and METALLICA has not accepted the offer or the period has
      expired in which METALLICA has to formalize the transaction, respectively,
      it shall transfer the NSR to the third party that made the offer at the
      same price and upon the same terms and conditions that are stipulated in
      the notification made to METALLICA in accordance with letter a) above or
      otherwise in terms more favorable for LOS POTRILLOS, but it shall never
      transfer the NSR in terms less favorable than those proposed to METALLICA.

c)    If LOS POTRILLOS does not transfer the NSR to a third party the NSR within
      the period stipulated in letter b) above, it is not able to effect such
      transfer subsequently, unless LOS POTRILLOS undertakes the same
      above-described procedure.

13. ASSIGNMENT

LOS POTRILLOS and METALLICA shall be authorized to assign all or part of their
contractual position in this contract to an affiliate, meaning only such company
in which LOS POTRILLOS and METALLICA or the head offices of both, own at least
51 % of the shares or interest in the same.

In the case of a total or partial assignment of this contract to any affiliate,
the assignor shall inform in writing the assigned party by way of a registered
letter sent through a Notary Public within ten days from the date of the
assignment.

In the event that either of the parties to this contract wishes to assign,
totally or partially, their contractual position in this contract or any of the
rights or credits

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arising from the same to a person distinct from an affiliate company, it shall
firstly make the offer to the other party to this contract, who shall have the
preferred right or option to acquire it in conditions that are agreed and in the
event of any offer to purchase by a third party in good faith extraneous to the
parties, upon equal conditions to the said interested party. For the
aforementioned purposes the party that it wishes to assign the contract shall
notify this fact in writing to the other party, indicating the conditions upon
which the assignment will take place and in the case of having an offer from
unrelated third parties in good faith, particularizing the information to the
interested party and providing all relevant information, such as price, period
of payment, etc. Upon receipt by the other party, it shall have the period of 30
working days from the date of receipt of the notification of the offer to
respond to it, indicating if it is willing to acquire the contract in the
conditions anticipated for the purposes of formalizing the respective
transaction within the maximum period of 60 working days. In the event that the
party receiving the offer does not accept it, it shall be understood that it has
waived the exercise of the right conferred upon it. In the event that it rejects
the offer in the terms previously stated, the offering party shall be released
from the provisions established in this clause, so that it may freely assign
this contract. The assignment shall only be opposed by the assigned party in the
event that the assigned, whatever may it be, is obliged in the corresponding
instrument of assignment to fulfill all and each one of the obligations that
arise from the present instrument.

14. EXCHANGE RATE

For all purposes of the payment of the sums stipulated in this instrument, the
amounts expressed in dollars of the United States of America shall be converted
into Chilean national currency (pesos) in accordance with the exchange rate
named "observed" published by the Central Bank of Chile, corresponding to the
day prior to the date of effective payment, or if the said exchange rate does
not exist, in

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accordance with the exchange rate that replaces it or better reflects the
exchange rate between the dollar of the United States of America and the Chilean
peso. The payment of each one of the installments of price shall be effected at
the domiciles that the Notary Public authorizes by way of deed, against the
signature of a public deed of receipt that the representative of the Property
Owner shall sign. In any event, full and timely compliance with the payment
obligation of each installment will be effected upon delivery to the Notary
Public that authorizes this deed, or its successor or replacement, of a check,
bank bond or term deposit at the order of the Property Owner, in Chilean
national currency (pesos) for the total of each installment or the balance of
the price pending as stipulated in Clause 10 as of the date when the Beneficiary
pays the installment or otherwise exercises the option, as calculated in the
form anticipated in this clause. The Notary Public shall deliver the
corresponding check, bank bond or term deposit to the representative of the
Property Owner or the person whom is delegated to sign the corresponding deed of
receipt. It shall use the same exchange rate and form of calculation to
determine and certify the investment which METALLICA is obliged in order to
maintain this contract in force, but for these purposes it shall use the average
value of the observed dollar in the month when the investment was made.

15. EFFECTIVE DELIVERY FOR EXPLORATION

METALLICA as at the time of entering into this deed shall effect the payment of
the installment referred to in number ONE of Clause 10, being expressly
authorized:

One) In order that its employees, contractors, subcontractors, employees and
other dependants have permanent and completely unrestricted access to the areas
covered by the Mining Property object of this contract and may carry out on them
all works and studies that it considers necessary.

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Two) To carry out all types of recognition, exploration, sampling, prospecting
works and, in general, to carry out all types of research or mining development
works that permit a qualitative and quantitative evaluation of the minerals
existing on the Mining Property, being authorized for such effect to introduce
onto such Mining Property all types of equipment and machines, of their own or
of third parties, to effect all labors mentioned or other works that are
necessary for the aims and objectives as indicated, whether directly or through
other companies that are contracted for such purposes.

Three) To carry out all works that it considers convenient or necessary to
evaluate the characteristics of the place where the Mining Property material of
this contract is located.

Four) The parties expressly state that the operations that are authorized by
virtue of this contract do not include, consequently, commercial exploitation
works of the said mining concessions. Notwithstanding the aforementioned,
METALLICA shall own all minerals that are extracted as a result of exploitation
works.

In the event that METALLICA decides not to exercise the option or it is
terminated by reason of one of the causes as set forth in Clause 8, it is
obliged to: ONE. Deliver to LOS POTRILLOS, within the period of 90 days from the
date of any of the facts mentioned above, without any cost to the Property
Owner, a copy of all geological, geochemical, geophysical information, samples,
drillings, trenches, perforations, grades and maps obtained with respect to the
Area of Interest and, in general, a copy of all data obtained and feasibility
studies or others carried out with the purpose or due to any exploration or
development program effected. TWO. Leave to the benefit of LOS POTRILLOS all
installations, constructions, improvements, works, tanks and other elements
located on the

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surface area of the Area of Interest, unless they can be withdrawn by METALLICA
without detriment or destruction of the same, nor of tunnels and/or holes that
may be constructed during the exploration. Such withdrawal shall be effected by
the Beneficiary within three months following the date in which the decision not
to exercise the option offered is communicated or is understood to have been
made, being obliged, at its own cost, to effect the environmental impact
statements or studies relevant to the abandonment of works, if there are norms
applicable to such objective.

16. PROHIBITIONS

LOS POTRILLOS constitutes a voluntary prohibition not to encumber or enter into
any deeds or contracts in respect of the Mining Property set forth in clause 1,
without prior consent, express and in writing of METALLICA, whose registration
in the Registry of Prohibitions of the respective Conservator of Mines shall be
required by the bearer of the authorized copy of the deed. The aforementioned is
notwithstanding the registration of this contract in the Registry of Mortgages
and Encumbrances in accordance with Article 169 of the Chilean Mining Code.

17. OTHER RIGHTS

If during the force of this contract the Beneficiary estimates that it is
necessary or convenient to request exploration or exploitation mining
concessions, water use concessions, civil and mining rights of way, concessions,
bailment or surface land rights within the Area of Interest, METALLICA shall
bear all related costs, understanding that these expenses form part of the
Exploration Expenses for all

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legal purposes. In the event that the option contract is terminated for any
reason, the concessions or rights that have been obtained in respect of the
lands covered by the Area of Interest, shall be transferred to the Property
Owner without any cost to the latter. In any event, LOS POTRILLOS and its
shareholders, directly or through third parties, shall request water rights,
rights of way or other mining rights in the Area of Interest object of this
contract.

18. PERMITS

In the event that METALLICA, in fulfillment of legal norms or if it considers it
necessary for the development of explorations, shall request special permits or
rights of access, transit or operation, whether in accordance with environmental
legislation, mining or other, and obtaining such permits infers or suspends the
exploration works which METALLICA is authorized to conduct by this contract, the
said period of the delay in obtaining the permit shall not be taken into account
for the purposes of the validity of this contract and during such period all
obligations assumed by METALLICA pursuant to this option contract shall be
suspended, such as for example, payment of option installments, effecting
Exploration expenses and any other obligation assumed by METALLICA, except for
payment of the mining patents that are covered by the Mining Property, in
respect of which METALLICA remains obliged.

The parties understand and expressly agree that if these suspensions occur, the
terms established in Clause 4, in respect of Exploration Expenses, Terms and
Amounts to Invest; Clause 7 about Term to exercise the option to purchase and
Clause 10 about Price of the Purchase Offer, shall automatically be extended for
an equal period without the need to enter into a complementary deed reflecting
the same.

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If the Property Owner requires the work to be carried out and it interferes or
suspends the exploration works authorized to METALLICA, the same rule shall be
applied as previously; on the contrary, that is, if obtaining these permits does
not interfere or suspend the exploration works, in any event the obligations
assumed by METALLICA in this contract shall be suspended, whether the process is
undertaken by the Property Owner or the Beneficiary. In any event, overlooking
the reason that has caused the interruption of the exploration works, once the
delay has been overcome the obligations imposed by this contract on METALLICA
shall be resumed.

In any event, and for the purposes of this clause, there shall be an
interference or suspension of exploration works if the process of obtaining the
permits takes more than 90 days and, as a consequence of it, METALLICA can not
develop any type of exploration works.

LOS POTRILLOS shall provide reasonable collaboration and assistance as required
by METALLICA in order to obtain the permits and authorizations that are required
to develop the exploitation works that are referred to in this contract.

19. FORM OF SALE AND VALIDITY OF TITLE

The Mining Property shall be sold as an entire body, in its current state, with
all uses, practices, rights and rights of way, active and passive and free of
mortgages, encumbrances, prohibitions, litigation, restrictions, sale and
purchase contracts of minerals in situ, leases, or any other type of deeds,
contracts, encumbrances, real and personal rights that impede the free use,
enjoyment, disposition and delivery of the Mining Property individualized in
Clause 1 and in the same conditions stated in Clause 2. The Property Owner shall
be liable for the validity of the titles in accordance with the law.
Furthermore, and in the event of METALLICA

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exercising the option, LOS POTRILLOS expressly waives the resolutory action that
arises in its favor as a consequence of the pending balance of payment that may
mean the Payment of the NSR established in Clause 11 previously, whatever being
the form of this payment that is finally adopted, however, with the exception
that LOS POTRILLOS may make a claim according to law to demand the payment of
this obligation, plus legal interest corresponding and the collection of all
costs associated with the said action.

20. OBLIGATIONS FOR THE BENEFICIARY.

METALLICA shall not carry out exploitation labors on the Mining Property,
subject matter of this contract, while it has not exercised the option, with
exception to those necessary to obtain samples or for metallurgic tests. In the
event of termination of this option contract, METALLICA shall have the period of
three months to abandon the concessions and withdraw from them all machines,
equipment and constructions that it has introduced. If it does not do so, the
parties shall proceed as set forth previously in Clause 14. In the event that
METALLICA is impeded from abandoning and withdrawing the machinery, due to
climatic conditions or other reasons of force majeur, the period indicated shall
be extended by a reasonable period taking into account the impediment.

21. PROTECTION OF MINING PROPERTY.

METALLICA, Beneficiary of this contract, shall assume the obligation of
protecting the Mining Property, object of this contract, through the full and
timely payment of the respective mining patents from the date of entering into
this contract and all those which accrue with respect to the following periods
in which this contract is maintained in force. As previously indicated, upon
execution of this

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contract METALLICA shall pay to LOS POTRILLOS the proportional part of the
mining patents corresponding to the period 2004-2005. In the event that LOS
POTRILLOS pays all or some of the mining patents in respect of the Mining
Property that is covered by this contract, in accordance with the same it shall
be the responsibility of METALLICA, in any respective period, to reimburse the
Property Owner, completely and duly for such payments, within the period of 15
days following the receipt of the respective proof of payment that for this
purpose shall be delivered by LOS POTRILLOS.

While this option contract is valid and in force, it shall be the responsibility
and cost of LOS POTRILLOS to maintain the control and protection of the area
corresponding to the Mining Property, with the purpose of maintaining it in
force and free of superpositions or third party rights. In such sense, it shall
exercise all rights and actions that the Chilean Mining Code confers upon it as
titleholder of the concessions and mining rights. If LOS POTRILLOS is informed
by the Beneficiary of a superposition or other situation that may affect the
validity of the Mining Property and the former does not exercise the actions
that legally correspond, the Beneficiary shall be authorized to exercise them
for the benefit of the Property Owner. For such purpose, the Property Owner
grants to the Beneficiary a power of attorney as broad as necessary with the
purpose that it exercises the actions and rights that correspond to the Property
Owner as titleholder of the Mining Property. The Beneficiary shall be especially
authorized to present oppositions to the survey or the constitution of mining
property; present claims of nullity of mining concession; request "demasias"
and, in general take all steps and presentations relevant to the control and
protection of the Mining property.

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22. APPLICABLE LAW.

This contract, the deed of acceptance of the offer and any amendments to the
aforementioned, shall be governed by the laws of Chile. Furthermore, the parties
understand and agree that if there is any conflict between this exploration
contract and the option with its annexes, the contract of exploration and option
shall prevail.

23. NOTARY EXPENSES AND REGISTRATION

The expenses and rights that are generated due to this contract and the
acceptance of the option, the corresponding deeds of receipt, release of
encumbrances, if any, and the reduction to public deed of the certificates
indicated in clause 8, if any, as well as the registration of rights in the
respective Mining Conservator, shall be borne by METALLICA. The latter shall not
be responsible in any event for the taxes and other personal charges that the
Property Owner incurs by reason of the option and the exercise of the option to
purchase as referred to.

24. JURISDICTION AND COMPETENCE.

All disputes that arise between the Property Owner and the Beneficiary or its
successors related to the interpretation, application, fulfillment, validity,
force, resolution, scope or force of this option contract, the acceptance or the
sale and purchase contract proposed, shall be resolved by the Ordinary Courts of
Justice of Santiago, Chile, being competent to act in these matters.

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25. COMMUNICATIONS.

All communications between the parties, except for those which are specially
designated in this contract, shall be made by facsimile followed by a certified
or registered letter to the domiciles indicated in this contract.

26. DOMICILE

For all purposes of this contract, the parties fix their domicile as the city of
Santiago, expressly submitting to the competent judicial organs.

27. AUTHORIZATION.

The bearer of an authorized copy of this deed and that which contains the
acceptance of the sale and purchase contract offered is authorized to request
and sign all the registrations, sub-registrations, annotations, certificates and
other actions that are proper or necessary with respect to the relevant
Registers or corresponding Registries. The appearing parties also authorize the
attorney Pablo Mir Balmaceda, acting on behalf of METALLICA and Juan Esteban
Perez-Barros Ramirez, acting on behalf of LOS POTRILLOS, so that any of them,
acting separately or indistinctly, can execute one or more minutes or public
deeds that replace deficiencies, defective designations or insufficiencies in
titles, in accordance with that set forth in article 82 of the Regulations of
the Real Estates Registry. The concession of these powers is, of course,
irrevocable.

THE LEGAL REPRESENTATION OF OAVALDO CAYTIN MORUNA TO ACT IN NAME AND
REPRESENTATION OF SOCIEDAD CONTRACTUAL MINERA LOS POTRILLOS is stated in the
document executed on May 17, 2004, before Luis Alberto Contreras Fuentes, Notary
Public of Copiapo, document that was presented to the Shareholders' Meeting of
the company on the same date.

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THE LEGAL REPRESENTATION OF PABLO MIR BALMACEDA TO ACT IN NAME AND
REPRESENTATION OF MINERALS METALLICA LIMITADA. is stated in the power of
attorney executed in Colorado, United States of America, on September 19, 2001,
that was duly legalized on November 5, 2001, before Notary Public of Santiago,
Ivan Torrealba Acevedo.

The powers of attorney referred to herein are not inserted as being known by the
parties and the Notary Public who is authorizing the same.

/s/ Osvaldo Cautin Moruna
Osvaldo Cautin Moruna
CIN# 5.364.859-2
Sociedad Copntractual Minea Los Potrillos

/s/ Pablo Mir Balmaceda
Pablo Mir Balmaceda
CIN# 6.374.989-3
Minera Metallica Limitada

/s/ Max Ringeling Hunger
Max Ringeling Hunger
Notary Public

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                                     ANNEX A

                                     ROYALTY

For the purposes of the mining option contract entered into by and between LOS
POTRILLOS and METALLICA, executed on the same date in the offices of Jose
Musalem Saffie, Notary Public, it is understood by:

1.-   "NET SMELTER RETURN" OR NSR: Shall consist of the total amount of money
      received by METALLICA or the concession holder, which origin is the sale,
      of other form of disposition, of copper, gold, silver, and molybdenum
      stemming from the treatment of minerals and substances extracted from the
      Mining Property, object of this contract,

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      and obtained by diverse refining processes of METALLICA, related companies
      or third parties.

      Such amounts of money shall only DISCOUNT:

      A)    All effective charge and costs, including transport, insurance
            corresponding to transport of the products from the processing plant
            on or near to the Mining Property to the place of sale, whether the
            product is transported by METALLICA, related companies or third
            parties.

      B)    All effective charge, cost, discount and fines by way of refining
            and smelting the products after such products have been withdrawn
            from the processing plant located on or near the Mining Property.

      C)    Ad valorem or royalty charges, VAT (or IVA as referred to in Chile)
            or any other similar tax, excluding Income Tax, paid to Chilean
            authorities (Treasury or other similar entity), stemming from laws,
            decrees, instructions, resolutions or any other requirement imparted
            by the Chilean Internal Revenue Service (Servicio de Impuestos
            Internos) for products extracted from the Mining Property.

      To such amounts of money, they shall add credits for sub-products, such as
      gold, silver and molybdenum, if any.

2.-   For all purposes of the payment of the royalty, the price of fine copper,
      Grade A, of the London Metal Exchange (LME Settlement) shall be used as a
      reference.

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3.-   LOS POTRILLOS shall have the right to audit all information used to
      determine the said payments, such as: geologic studies of reserves and
      laws; accounting registers exclusively associated with the determination
      of the production costs of the substances from the Mining property; sale
      contracts and credits for sub-products; invoices issued; processing costs
      and all supporting information; metallurgic balance and supporting
      documentation and contracts entered into with related entities and third
      parties. In any case the exercise of this right shall affect the normal
      development of the activities or processes of the Beneficiary.

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