Aluminum is a silvery white and ductile member of the boron group of chemical elements. Aluminium is remarkable for its ability to resist corrosion due to the phenomenon of passivation and the metal's low density. Structural components made from aluminium and its alloys are vital to the aerospace industry and very important in other areas of transportation and building. Aluminium is a soft, durable, lightweight, malleable metal with appearance ranging from silvery to dull grey, depending on the surface roughness. Aluminium is nonmagnetic and nonsparking. Aluminium is 100% recyclable without any loss of its natural qualities. Recovery of the metal via recycling has become an important facet of the aluminium industry. Aluminium is the most widely used non-ferrous metal.