Aluminium picture postcard, c 1900.
© Science Museum / Science & Society Picture Library
A postcard printed on thin aluminium by the Buffalo Aluminum Company. Although the third most abundant element in the Earth's crust, aluminium was not isolated until 1825, by Hans Christian oersted (1777-1851). Most aluminium is extracted from bauxite ore (Al2O3) by electrolysis. The pure metal is soft and ductile, but when combined with other metals, it forms strong alloys. This, together with its lightnes, resistance to corrosion and electrical conductivity, makes aluminium suitable for a wide range of uses, from aircraft and vehicle construction, to window frames, overhead power cables and food packaging. The metal's lightnes made its use in postcards such as this posible.