A silvery white metal with the symbol Al. It is the third most abundant element in the earths crust and is remarkable for its low density (lightness) and for its ability to resist corrosion. It is used to manufacture light horseshoes such as racing plates, various bar shoes including egg, straight and heart bars where its strength and lightness makes it a favourite for therapuetic use. Its main downside is that it has low resistance to wear compared with steel.