Aluminum or aluminum (Aluminium) is the chemical element symbol Al and atomic number 13. It is a Argyrolefkes metal element belonging to the group IIIA (13) of the periodic system with boron. It is the most abundant metal in the Earth's crust and overall the third (3rd) most abundant chemical element in the whole planet after oxygen and silicon. When weight is approximately 8% of the crust. However it is very reactive chemically to found in nature as a free metal. Conversely, is bonded to more than 270 different minerals . The main source for industrial production of the metal is bauxite.
The metal aluminum has (seemingly) great ability to resist corrosion. This essentially is because the exposure of the metal in the atmosphere forms briefly one minute surface, invisible, layer of oxide, which prevents deeper erosion (phenomenon of passivation). Also, because of its relatively low density and large capacity to create great variety of alloys, became a strategic metal for the aerospace industry (and not only) industry. It is also extremely useful in the chemical industry, such as such as a catalyst, and in the form of various associations.