The structure of the US copper and copper alloy industry has undergone dramatic changes over the last ten or twenty years. In 1966, for example, the United States was by far the largest producer of newly mined copper, as well as the largest consumer. In addition, US companies accounted for most of the output of the copper mines in South America, chiefly Chile and Peru, thus representing effective US control of about 45% of free world production.
The US-owned mines in Chile began to be nationalized in the late 1960s, and the government of Chile has greatly expanded their output. Today the US share of world mine production is about 18%. Chile has over a 23% share, nearly all of which is exported, and has the largest copper reserves in the world. Other important producers are, in order of mine production, Russia, Canada, China, Australia, and Zambia.