Peru Copper (CUP) SC TO-T Third party tender offer statement

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OFFER TO PURCHASE FOR CASH

all of the outstanding common shares of
Peru Copper Inc.

for

Cdn$6.60 per common share

by

CHINALCO CANADA B.C. HOLDINGS LTD.

a wholly-owned subsidiary of

ALUMINUM CORPORATION OF CHINA

THE OFFER WILL BE OPEN FOR ACCEPTANCE UNTIL 12:00 NOON
(TORONTO TIME) ON JULY 31, 2007 (THE "EXPIRY TIME"),
UNLESS EXTENDED OR WITHDRAWN BY THE OFFEROR.

To Our Clients:

        Enclosed for your consideration are the Offer to Purchase and Circular dated June 25, 2007 and the related Letter of Transmittal and Notice of Guaranteed Delivery (collectively, the "Offering Documents"), in connection with the Offer by Chinalco Canada B.C. Holdings Ltd. (the "Offeror"), a company incorporated under the laws of the Province of British Columbia and a wholly-owned subsidiary of Aluminum Corporation of China, to purchase for cash all of the issued and outstanding common shares (the "Common Shares") of Peru Copper Inc. at a purchase price of Cdn$6.60 per Common Share upon the terms and subject to the conditions set forth in the Offering Documents.

        Capitalized terms used but not defined in this letter have the meanings set forth in the Offering Documents.

        We are the holder of record of Common Shares for your account. A deposit of such Common Shares can only be made by us as the holder of record and pursuant to your instructions. The enclosed Letter of Transmittal is furnished to you for your information only and cannot be used by you to deposit Common Shares held by us for your account.

        We request instructions as to whether you wish us to deposit any or all of the Common Shares held by us for your account, upon the terms and subject to the conditions set forth in the Offering Documents. Your attention is directed to the following:

1.

The Offer price is Cdn$6.60 per Common Share.



2.

The Offer is being made for all of the issued and outstanding Common Shares.



3.

The Offer will be open for acceptance until 12:00 noon, Toronto time, on July 31, 2007, unless extended or withdrawn.



4.

Depositing Shareholders will not be obligated to pay any brokerage fee or commission to the Depositary or the U.S. Forwarding Agent to accept the Offer.



5.

The Offer is subject to certain conditions, including, without limitation, there being validly deposited under the Offer and not withdrawn, at the Expiry Time, not less than 66²/3% of the Common Shares outstanding at the Expiry Time (on a fully-diluted basis, excluding Common Shares held by the Offeror or its affiliates). The conditions of the Offer are set forth in Section 4 of the Offer to Purchase, "Conditions of the Offer". Subject to applicable law, the Offeror reserves the right to withdraw the Offer and not take up and pay for any Common Shares deposited under the Offer unless each of the conditions to the Offer is satisfied or waived by the Offeror prior to the Expiry Time.

        The Offer is made solely through the Offering Documents and is not being made to, nor will deposits be accepted from or on behalf of, Shareholders in any jurisdiction in which the making or acceptance of the Offer would not be in compliance with the laws of such jurisdiction.

        If you wish to have us deposit any or all of your Common Shares, please so instruct us by completing, executing and returning to us the instruction form accompanying this letter. An envelope to return your instructions to us is also enclosed. If you authorize the deposit of your Common Shares, all such Common Shares will be deposited unless otherwise specified on the reverse side of this letter. Your instructions should be forwarded to us so as to provide us with ample time to submit a deposit on your behalf prior to the Expiry Time.

INSTRUCTIONS WITH RESPECT TO THE
all of the outstanding common shares of
Peru Copper Inc.
for
Cdn$6.60 per common share
by
CHINALCO CANADA B.C. HOLDINGS LTD.
a wholly-owned subsidiary of
ALUMINUM CORPORATION OF CHINA

        The undersigned acknowledge(s) receipt of your letter, the Offer to Purchase and Circular dated June 25, 2007, and the related Letter of Transmittal and Notice of Guaranteed Delivery (collectively, the "Offering Documents") in connection with the Offer by Chinalco Canada B.C. Holdings Ltd. (the "Offeror"), a company incorporated under the laws of the Province of British Columbia and a wholly-owned subsidiary of Aluminum Corporation of China, to purchase for cash all of the issued and outstanding common shares (the "Common Shares") of Peru Copper Inc. at a purchase price of Cdn$6.60 per Common Share upon the terms and subject to the conditions set forth in the Offering Documents.

        The undersigned hereby instructs you to deposit to the Offeror pursuant to the Offer the number of Common Shares indicated below that are held by you for the account of the undersigned (or, if no number is indicated below, all such Common Shares held by you for the account of the undersigned), upon the terms and subject to the conditions set forth in the Offering Documents.

Number of Common Shares to be Deposited:*	Account No.(s):
Dated:
	Signature(s)
	Print Name(s) and Address(es)
	Area Code and Telephone Number(s)
	Taxpayer Identification or Social Security Number(s)

*

Unless otherwise indicated, it will be assumed that all Common Shares held by us for your account are to be deposited.

2

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OFFER TO PURCHASE FOR CASH all of the outstanding common shares of Peru Copper Inc. for Cdn$6.60 per common share by CHINALCO CANADA B.C. HOLDINGS LTD. a wholly-owned subsidiary of ALUMINUM CORPORATION OF CHINA THE OFFER WILL BE OPEN FOR ACCEPTANCE UNTIL 12:00 NOON (TORONTO TIME) ON JULY 31, 2007 (THE "EXPIRY TIME"), UNLESS EXTENDED OR WITHDRAWN BY THE OFFEROR.
INSTRUCTIONS WITH RESPECT TO THE all of the outstanding common shares of Peru Copper Inc. for Cdn$6.60 per common share by CHINALCO CANADA B.C. HOLDINGS LTD. a wholly-owned subsidiary of ALUMINUM CORPORATION OF CHINA