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Home | Odds and Ends: The discovery of aluminium smelting

In the nineteenth century Charles Martin Hall and Paul Louis Toussaint Héroult did not know of each other's existence.

They both simultaneously discovered the solubility of alumina in the mineral cryolite which at the time was only found beside a certain fjord in Greenland.

Cryolite (Na3AlF6 sodium hexafluoroaluminate) is an uncommon mineral of very limited natural distribution. (Wikipedia).

Héroult applied for a patent in France in April 1886. Hall filed for a US patent in July 1886 (the process has become universally known as the Hall - Héroult process)

Both men were born in 1863.

Both were 22 at the time of their invention.

Both men died in 1914 at the age of 51.