Page 4 of 11   

This Amendment No. 2 amends and supplements the Schedule 13D (“Schedule 13D”) filed by the following entities (collectively referred to herein as the “Reporting Persons”, and each as a “Reporting Person”) with the U.S. Securities and Exchange Commission (“SEC”) on July 8, 2005, as amended and supplemented by Amendment No.1 filed with the SEC on July 27, 2007:

Rio Tinto plc, a public limited company incorporated under the laws of England and Wales (“Rio Tinto”), is an international mining company with operations around the world. Rio Tinto’s principal executive offices are located at 6 St. James’s Square, London, SW1Y 4LD, England.

Kennecott Canada Exploration Inc., a corporation incorporated under the laws of Canada and an indirect wholly owned subsidiary of Rio Tinto (“Kennecott”), is a mining company the principal business of which is the discovery and acquisition of mineral resources in North and Central America. Kennecott’s principal offices are located at 200 Granville Street, Suite 354, Vancouver, British Columbia, V6C 1S4, Canada.

The name, business address, present principal occupation or employment and citizenship of each of the executive officers and directors of the Reporting Persons are set forth in Schedule I hereto and are incorporated by reference herein.

During the last five years, neither of the Reporting Persons and, to the knowledge of each of the Reporting Persons, none of the persons listed in Schedule I hereto has been: (i) convicted of a criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

Item 3 of Schedule 13D is hereby amended and supplemented by adding the following additional paragraph after the fifth paragraph:

On November 9, 2007, Kennecott elected to exercise in full its preemptive, anti-dilutive rights under section 2.4 of the EPA with respect to the purchase of common shares of the Company by BMO Nesbitt Burns Inc., as underwriter. As a result, on November 26, 2007, Kennecott purchased 2,300,284 Common Shares of the Company at a price of C$3 per Common Share, for a total consideration of C$6,900,852. These shares were purchased using working capital of Rio Tinto. Following completion of the transaction, the Reporting Persons own