Ores of Copper
September 25, 2009
Chemists and mineralogists know that copper compounds are some of the most colorful natural substances. This photo shows sample of copper ore (about 2 in. or 5 cm across) from the remote ghost town of Copperopolis, in central Arizona. The greenish mineral is malachite (CuCO3*Cu(OH) ), and the bluish mineral is mostly chrysocolla (CuO*SiO2*2H2O ). Both are common ores of copper.
Copper mining has always been a difficult business. Mining at Copperpolois started in 1883. Before that time, conflicts with the Yavapai Apaches made these remote locations very dangerous. But the scattered copper deposits and low-grade ore led to the closing of the Copperopolis operation after less than ten years. Today, Arizona produces more copper ore than any other state in the U.S. The largest mine is at Morenci, which yields about 30% of the total U.S. production. Recent demand, fueled partly by economic growth in Asia, quadrupled the price of copper between 2002 and 2008. But the current recession has nearly wiped out those gains. Investors beware. Photo taken on March 9, 2009.