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COPPER Copper is a naturally occurring element that is not radioactive. It has a bright, metallic luster, and a hardness of three. It takes on a cubic crystal structure, with a density of 8.96. Copper is malleable, ductile, and a very good conductor of heat and electricity, second only to silver. This natural resource melts at 1,083 degrees celcius and boils at 2,567. If you ever feel like boiling copper at home, I recommend a very big oven. All copper falls into two main categories: oxidized or sulfide ore. Both of these ores can be taken from the ground by open-pit, or underground mining. The oxidized ores can have the copper extracted very easily by heating it with carbon in a furnace. Sulfide, on the other hand, is much more difficult. First the ore must be crushed into powder, and dumped into a big tank. Then, since a special mixture has been added to the water, all the copper floats to the surface. It is skimmed off, and hearted with silica. After being heated, the top layer of silica is taken off, and the bottom is the copper. Those are the two ways in which copper is refined. In the times of the ancient Romans and Greeks, most of their copper was mined on the Island of Cyprus. Today copper is produced from many places around the world. Among them are Poland, Chile, Peru and the United States. Over 160 minerals with copper in them have been discovered. This mineral is present in one part of the earth s crust for every 14,285 parts. That means that copper is common, but not abundant.

Copper is widely used in commercial businesses and machinery. The metal is used to carry electrical power in generators and batteries. Since it is also resistant to rust, it is used in car radiators, and in chemical plants as well. Also, probably the most well known use for copper, is tubing and pipes used in both residential and commercial plumbing. Another use of copper was in the creation of the penny. To a lesser extent, copper is also used in making jewelry, cooking utensils and decorative pieces. Some people believe that wearing a copper bracelet helps fight the pain of arthritis. In 1982, the use of copper fell from 2.2 tons per year to 1.6 tons. This decline was caused by the plumbing industry switching to plastic for making pipes, and by car manufacturers using aluminum in the place of copper. As a result, one of the largest open-pit mines in Butte, Montana closed down. That caused a loss of 18,000 jobs over a two year period. As quickly as the business fell, it recovered. In 1988, the use of copper in the United States sky-rocketed. Copper wire was used for electronics, and industrial machinery also began switching to this amazing element. Although copper is a highly sought after natural resource, no one has been able to artificially produce it in great quantities.


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