Bar of aluminium, c 1855.
© Science Museum / Science & Society Picture Library
Given to English chemist and physicist Michael Faraday (1791-1867), by the wish of Napoleon III, after aluminium was first produced in bar form in 1855. Faraday added the string to demonstrate resonant qualities. 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.