What is Aluminum?

Alumunium is a silvery-white, lustrous metal that is only about one-third as heavy as iron. It can be drawn out into wires that are finer than the finest hairs, and hammered into sheets as thin as a sheet of newspaper. It may surprise you to learn that is the most abundant of all the metals in the world.

Nearly 8 percent of the earth’s crust is alumunium. But alumunium is never found free in nature. It is combined with various substance to form parts of many rock and soils. Did you know that sapphires, rubies, garnets, and other beautiful gems are compounds of alumunium?

The problem was how to separate cheaply alumunium from the other substances. On February 23rd, 1886, a twenty-two-year-old chemist named Charles Martin Hall found a way  to make this metal cheaply and in large quantities. In melted cryolite, which is a compound of alumunium oxide. Then he placed the mixture in a carbon vessel and passed a direct electric current through it.

After about two hours, little "buttons" of metallic aluminum were found in the bottom of the vessel. This same general method is still used for the productions of the world’s entire supply of aluminum metal. Cryolite is found only in Greenland, but can be manufactured if the mineral form is not available.

Bauxite, an impure aluminum oxide, is found in many countries, but must be purified before it can be used to produce metal. Aluminum is an almost perfect materials for cooking utensils because it is a good conductor of heat, and is easily kept clean and bright. It is also used in motor-car engines, aeroplanes, and train engines.   

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