The ancient Greeks and Romans used alum as an astringent and as a mordant in dyeing. In 1761, the alumina Morveau proposed name for the base of alum, and Lavoisier, in 1787, thought this to be a metal oxide yet discovered. Wohler is generally
credited with having isolated the metal in 1827, although an impure form was prepared by Oersted two years earlier. In 1807, Davy proposed the name aluminum for the metal, undiscovered at that time and later agreed to change it to aluminum. Soon after, the name was adopted in aluminum to comply with the "ium" at the end of most elements.
Aluminium was also the accepted spelling in the United States until 1925, when the American Chemical Society decided to use the name aluminum thereafter in their publications.
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Aluminum can now be produced from clay, but the process is not economically feasible at present. Aluminum is the most abundant metal found in the earth's crust (8.1%), but never found free in nature. In addition to the minerals mentioned above, it is also found in granite and many other common minerals.
Although its electrical conductivity is only about 60% that of copper, it is used in electrical transmission lines because of its light weight. Pure aluminum is soft and lacks strength, but alloyed with small amounts copper, magnesium, silicon, manganese, and other items give a variety of useful properties.
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