Specifications: Aluminium Aluminium or aluminum is a silvery white and ductile member of the poor metal group of chemical elements. It has the symbol Al; its atomic number is 13. It is not soluble in water under normal circumstances. Aluminium is the most abundant metal in the Earth's crust, and the third most abundant element overall, after oxygen and silicon. It makes up about 8% by weight of the Earths solid surface. Aluminium is too reactive chemically to occur in nature as the free metal. Instead, it is found combined in over 270 different minerals. The chief source of aluminium is bauxite ore. Aluminium is remarkable for its ability to resist corrosion (due to the phenomenon of passivation) and its light weight. Structural components made from aluminium and its alloys are vital to the aerospace industry and very important in other areas of transportation and building.
Scientists suspected than an unknown metal existed in alum as early as 1787, but they did not have a way to extract it until 1825. Hans Christian Oersted, a Danish chemist, was the first to produce tiny amounts of aluminum. Two years later, Friedrich Wöhler, a German chemist, developed a different way to obtain aluminum. By 1845, he was able to produce samples large enough to determine some of aluminum's basic properties. Wöhler's method was improved in 1854 by Henri Étienne Sainte-Claire Deville, a French chemist. Deville's process allowed for the commercial production of aluminum. As a result, the price of aluminum dropped from around $1200 per kilogram in 1852 to around $40 per kilogram in 1859. Unfortunately, aluminum remained too expensive to be widely used.
Two important developments in the 1880s greatly increased the availability of aluminum. The first was the invention of a new process for obtaining aluminum from aluminum oxide. Charles Martin Hall, an American chemist, and Paul L. T. Héroult, a French chemist, each invented this process independently in 1886. The second was the invention of a new process that could cheaply obtain aluminum oxide from bauxite. Bauxite is an ore that contains a large amount of aluminum hydroxide (Al2O3·3H2O), along with other compounds. Karl Joseph Bayer, an Austrian chemist, developed this process in 1888. The Hall-Héroult and Bayer processes are still used today to produce nearly all of the world's aluminum.
With an easy way to extract aluminum from aluminum oxide and an easy way to extract large amounts of aluminum oxide from bauxite, the era of inexpensive aluminum had begun. In 1888, Hall formed the Pittsburgh Reduction Company, which is now known as the Aluminum Company of America, or Alcoa. When it opened, his company could produce about 25 kilograms of aluminum a day. By 1909, his company was producing about 41,000 kilograms of aluminum a day. As a result of this huge increase of supply, the price of aluminum fell rapidly to about $0.60 per kilogram.
