The Canadian cordillera, consisting principally of British Columbia and Yukon, is rich in minable deposits of copper, zinc, lead, and molybdenum, and has nickel, tungsten, gold, silver, mercury, and iron deposits.

The cordillera shows a pronounced regional zoning of metals in background abundances in rocks and an associated zoning in class of deposits and contained metals. Sequential changes occur across the strike of the five subparallel tectonic belts.

The mineral industry has expanded rapidly in the last decade. The total value of metal production in 1973 was $839 million in contrast to $189 million in 1963. Production of major metals for the whole terrane in 1973 was copper, 730 million lb; zinc, 553 million lb; lead, 431.5 million lb; and molybdenum, 25 million lb.

For copper, the 1973 production represented about 8% in international trade. Production and reserves have greatly increased in this decade. For British Columbia geologic reserves at present rates of extraction are estimated to be sufficient for copper and molybdenum for 100 years, for zinc about 60 years, and lead about 35 years.

Mode of discovery has changed radically. Classical prospecting is still the most important method although it shares with more technical methods the revelation of actual significance. Of some 60 major mines and prospects discovered in the last 15 years, the primary discovery credit may be attributed as follows: classical prospecting, 50%; geologic deduction, 21%; geochemistry, 20%; geophysics, 9%.

Factors other than discovery, development, and markets are becoming increasingly important. The industry currently is based significantly on low-grade porphyry deposits most of which have no enriched zones. The profitability of such mines is marginal during periods of low metal prices. To survive, operations have had to become highly efficient. The task becomes more difficult in the face of new legislation in British Columbia and proposed legislation in Yukon. More stringent reclamation and environmental regulations and royalties and increased taxes are being applied. There is a hiatus in mine development awaiting clarification of the impact of the new laws, but exploration and discovery continue at a high level.

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