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Facts of the matter
Richard Brill
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Versatility makes copper a crucial metal
Copper is second only to gold as a metal known to mankind, dating back approximately 6,300 years. It has been one of the important materials in the development of civilization.
Thanks to its versatile and attractive properties of ductility, malleability, high thermal and electrical conductivity, and resistance to corrosion, even today copper is the most frequently used metal worldwide.
Copper has many uses, including power generation, wiring for buildings, transportation and telecommunication, circuitry for electrical and electronic products, plumbing, coinage, alloys and decorations. Electrical applications account for about three-quarters of total copper use.
Building construction is the single largest market, followed by electronics and electronic products, transportation, industrial machinery and consumer and general products. Recycling of copper byproducts and scrap metal contribute significantly to copper supply.
Copper is not a particularly abundant metal in Earth's crust. It is barely in the top 20 percent of abundant elements, but like most metals, it is concentrated in ore deposits from hydrothermal processes on an ancient sea floor. That sea floor now forms mountain ranges or is wedged between colliding continents like the island of Crete in the Mediterranean Sea.
Copper does occur in a chemically uncombined state and was mined as such for centuries. Now, however, it is depleted as an economically viable supply. Copper minerals made of chemical associations with sulfur are more economical to mine and purify into metallic copper.
Pure copper metal is generally produced from a multistage process involving smelting and electrolytic refining, although acid leaching techniques are becoming more widespread as the price of copper climbs.
Domestic mines recovered 160 million tons of ore in 2005 with a value of $4.4 billion from 14 mines, principally in Arizona, Utah and New Mexico.
Through 2007, demand for refined copper outstripped global demand, and global inventories of refined copper were down considerably despite a growth in world production of copper that exceeded a decline in copper consumption.
The Unites States produces about 8 percent of the global supply, which is consistent with the country holding about 7 percent of copper ore reserves.
Copper wire accounted for 75 percent of copper usage in the U.S. in 2005, of which 80 percent was recycled from scrap.
The price for copper -- as with any commodity -- is based on the market, and the price has increased by 87 percent since 2001, making copper theft and black-market trading a hot commodity in many areas around the globe, especially in Third World regions.
Much of the price increase is due to the rapidly expanding technological growth of Asia, with China now using 22 percent of the world's refined copper, an increase of nearly 10 percent per year. While mining and refining is increasing, China was the destination of 61 percent of domestic scrap exports and accounted for 71 percent of reported global scrap imports.
Richard Brill, professor of science at Honolulu Community College (
honolulu.hawaii.edu/~rickb), teaches earth and physical science and investigates life and the universe. His column is published on the first and third Sundays of every month. E-mail questions and comments to
rickb@hcc.hawaii.edu.