Charles Martin Hall

American chemist and inventor Charles Martin Hall had invented a process for obtaining aluminium from aluminium oxide.

In 1886 Charles Martin Hall was a twenty-two year old university student. One day in class, his chemistry instructor casually remarked that anyone who could devise a practical means of isolating aluminium from its ores would grow immeasurably rich. Hall, taking his teacher at his word, returned home where he kept a small laboratory and began to experiment.

Hall eventually devised a suitable method - and promptly grew rich. He worked in a woodshed using homemade and borrowed equipment. After about a year he found that aluminum oxide dissolves in molten aluminium fluoride (cryolite) to produce a solution from which aluminum can be made under electrolysis.

Hall passed an electric current through this solution to produce aluminum. The electric current came from electrochemical cells that he made from jars that his mother used to can fruit.

By an odd coincidence Paul Heroult, who was the same age as Hall, made the same discovery independently in France about the same time. As a result of the discovery of Hall and Heroult, the large-scale production of aluminum became economically feasible for the first time, and it became a common metal.

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ALUMIN I UM OR ALUMINUM?

The official international spelling of this metal includes the extra letter I. But Charles Martin Hall popularized the current US spelling without the letter I — apparently as the result of a simple misspelling on his patent application.