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                    This Amendment No. 1 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”), filed with the U.S. Securities and Exchange Commission (“SEC”) on July 8, 2005:

                    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 the Schedule 13D is hereby amended and supplemented by adding the following to the end of the third paragraph:

                    On June 27, 2007, the Reporting Persons exercised the warrants and, as a result, currently own 12,613,841 Common Shares (representing approximately 16.3% of the Company’s Common Shares). Upon exercise of the warrants, the Reporting Persons acquired 3,153,460 Common Shares at a price of C$ 2.75 per Common Share and 3,153,460 Common Shares at a price of C$3.00 per Common Share, for a total consideration of C$ 18,132,395, which was funded from intergroup loans.