PGE distribution in the New Afton Cu-Au porphyry deposit**

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Much of Canada's primary production of both copper and gold comes from deposits called alkalic porphyry deposits. These deposits are hosted by or associated with a type of igneous intrusion that is thought to be derived by melting of the mantle deep beneath the Earth's crust over subduction zones. Although these deposits are mined for copper and gold, the ores commonly contain minor amounts of the precious metals platinum and palladium. Consideration of the genesis of the magmas thought to be responsible for the formation of gold-rich alkalic porphyries suggests that these magmas should be at least as rich in platinum and palladium as they are in gold. Since the ores of copper and gold contain relatively low concentrations of platinum and palladium, the fate of these precious metals remains a mystery. The proposed project will systematically examine all of the rocks associated with a well-described copper-gold alkalic porphyry using precise and sensitive assay methods to detect platinum and palladium even at concentrations far below economic grades. The results will be used to attempt to detect and describe the behaviour of platinum and palladium in the porphyry deposit environment, with the aim of showing where the missing metal has been deposited. Since platinum and palladium are expected to have been present in the system initially, and they are not found in large amounts in the copper-gold ore, it is likely that they have been deposited in other nearby rocks affected by flow of hot fluids associated with the ore-forming system. Such deposits may turn out to be dispersed at such low concentrations that they are insignificant economically, however recognition of platinum and palladium ores is difficult because they are economically interesting at grades of only a few parts per million, far below levels at which the ore minerals are detectable with the naked eye. It is therefore also possible that high-grade zones of platinum and palladium will be encountered that have never previously been recognized. The work will provide New Gold Inc and other Canadian mining companies with new insight into the distribution of precious metals in Canadian mineral deposits.**