ALUMINUM

Aluminum is the third most abundant element in the earth's crust after oxygen and silicon and accounts for 8% of its composition by weight. It is the most common metal on earth, 800 times more common than copper, which has been used for thousands of years. Aluminum does not occur in its pure state in nature, but it is common in various compounds such as oxides, as well as in silicates such as feldspar, micas and clays. The main raw material used in aluminum processing is alumina, a compound of aluminum and oxygen. Alumina is processed from a clay-like substance called bauxite that occurs primarily along a broad belt across the equator. Aluminum is produced by a method called electrolysis. An electric current is used to break the alumina molecule into its elements.

Light and Strong
The specific gravity of aluminum is only one-third that of steel. By alloying with other metals such as copper, magnesium or manganese, it can be substantially hardened and strengthened.

Anti-Corrosive
On contact with oxygen, aluminum forms a thin transparent layer of aluminum oxide that protects the metal against corrosion. This coating can be made permanent by giving it a shiny finish, then painting and varnishing it.

Highly Conductive
Aluminum is a good electrical and thermal conductor, as well as an efficient reflector of light and heat. Moreover, aluminum has a low - and only temporary - susceptibility to magnetic forces.

Malleable
Aluminum has a melting point of only 660°C. It is highly fluid in its molten state and very malleable when either hot or cold.

Compact and Odorless
Aluminum foil, made solely from rolled aluminum, is 100% dense and impervious to light, odor and taste. And it has no effect on the taste or smell of food wrapped in it.

Non-Flammable
As a non-flammable substance, aluminum is ideal for construction and transportation. It only burns when powdered or very thin and does not generate gases upon combustion.

Recyclable
The low melting point of aluminum makes it very easy to recycle. Only 5% of the energy used for the primary processing of aluminum is required to recycle it. This is one reason that environmentally friendly aluminum is often called the "green" metal.

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