The Great American Expansion of Copper Mining

The major modern sources of the metal have been the two Americas and Central and Southern Africa.

The two great chains of the Andes with the high plateau of Peru between them are extraordinarily rich in metals - tin in Bolivia and silver, copper and gold in Peru and Chile, besides a number of other important economic minerals. Some of these mines were worked by the Incas, others were developed by the Spanish Conquistadores, but it was in the latter part of the 19th Century that mining first became a really large industry. Development has been continuous and new mines are being opened up today: well-known names are Cerro de Pasco, Chuquicamata, Braden, Corocoro, etc. Cerro de Pasco, situated at an altitude of 18,000 ft., is one of the highest mines in the world. At Chuquicamata, an enormous opencast pit, which is one of the largest in the world, has been excavated: mining on a serious scale only began there in 1879 under British impulse. The Chilean ore was at first exported to Swansea, but this ceased on the later construction of local smelters. It is worth recording that in an average year between the two World Wars - say, 1927 - 7 1/2 million tons of copper ore were dug out at Chuquicamata alone, which yielded 123,000 tons of copper.

The Braden mine at El Teniente, near Rancagua, Chile, is quite unique. It occupies the heavily mineralized core or plug of an extinct volcano.

The numerous large copper mines of the United States, which between them now produce roughly a million tons of copper every year, began to be exploited mainly in the 1850's. Development of the Canadian mines began chiefly at the turn of the century, and those of Zambia shortly after World War I. Many of the mine names are household words both in the industry and among investors, e.g. Roan Antelope, Mufulira, N'Changa, Anaconda, Kennecott, Chino, Miami, Sudbury, Noranda.

Whatever the metal, the life of any individual mine is generally limited, but some of the copper deposits are so extensive that they still have a long life ahead of them. Others are now merely famous names. The original Kennecott Mine, which was in Alaska, is a case in point. One of the longest-lived of the great copper mines has been Calumet and Hecla, with its fabulously rich deposits of native copper on the Keweenaw Peninsula of Michigan. Production began in 1865 and has been continuous ever since, although in recent years much of its copper has been derived by reclamation. By 1930 the annual total of copper yielded by this one mine was still next to the largest in the United States and the grand total at that date was just short of 1 3/4 million tons of refined copper alone.

For the great contributions towards the world's copper supplies that have been made in modern times by Canada and Zambia, see pages 76-78.

Australia and Tasmania also have valuable copper mines.