The industrial production of aluminium was not commercially viable until the concurrent discovery by a French chemist, Paul Louis Héroult (1863-1914), and an American, Charles Martin Hall (1863-1914), working independently of one another of an electrolytic process to reduce alumina (aluminium oxide) to produce the primary metal in 1886.
Prior to their discovery, the metal had been produced using exclusively chemical processes but in such quantities (and at such expense) that it was not financially feasible to market the metal. The Hall-Héroult process was complemented by the discovery, by the Austrian chemist Karl Josef Bayer (1847-1904), of an efficient chemical process for extracting alumina from bauxite (the naturally occurring mineral from which aluminium is derived) between 1887 and 1892.
Hall and Héroult’s discovery was also aided by the electrical revolution. The reduction process used in British Aluminium’s Highland reduction works used the Héroult process (which is marginally different from Hall’s). In the interests of clarity, it is worth pointing out that terminology varies internationally in the aluminium industry.