A pot of Persian design
It is often said that Aluminum has had a relatively brief history, and under the name Aluminum it is certainly true. But using aluminum for its properties in compounds (some sources reckon) started at around 5300 BC. It is thought that potters in ancient Persia made their strongest cooking vessels from a clay that consisted largely of aluminum silicates. Aluminum compounds are thought to have been used more by the Egyptians and Babylonians around 4000 years ago as fabric dyes and cosmetics.
Red clay containing bauxite
Despite these uses in the very far past the element aluminum itself wasn't discovered or named until the early 1800's when Sir Humphrey Davy established its existence, but even he was unable to actually make any. Just over 10 years later a French scientist discovered hard, red clay containing over 50% aluminum oxide in southern France. It was named bauxite, aluminum's most common ore (see abundance
for more bauxite information). As aluminum is so combined in nature, and never occurs naturally, even up to this time no pure aluminum had been produced.
In 1825 a small lump of aluminum metal was finally produced by Hans Christian Oersted of Denmark, whose work was continued and developed by Friedrich Wohler in Berlin who managed to isolate aluminum as a powder in 1827, in a process involving potassium and anhydrous aluminum chloride. Wohler also established the density of aluminum, and discovered its key lightness in 1845. Nine years later, another French scientist, Henri Sainte-Claire Deville, became involved with aluminum, and improved upon Wohler's method to create the first commercial production process.
Hall / Heroult.
At this time aluminum was more expensive than gold and platinum1
, and it was regarded as "the new precious metal". A bar of aluminum was even exhibited at the Paris Exhibition in 1855. But over the next ten years its value fell by over 90% although it was still far too expensive to be adopted by industry as the metal of choice. Gradually methods were improved upon and in 1885 a process was developed with an annual output of 15 tonnes. The real revolution occurred a year later with the remarkable, separate but simultaneous development of an aluminum isolation method on either side of the Atlantic. Paul Louis Toussaint Héroult of France and Charles Martin Hall of the USA both came up with a process of dissolving aluminum oxide in molten cryolite (to lower the melting point and therefore the energy required) and passing through a large electrical current. When this was done pure aluminum collected at the bottom. The process was named after both scientists and we still use the Hall Herout Method
Growth of Aluminum Production
In 1889 Karl Josef Bayer developed a new, more efficient process (the Bayer process
) for the extraction of aluminum oxide from bauxite. Again the price of aluminum fell. The quantities of aluminum produced began to grow. In 1900 8 thousand tonnes were produced, in 1946 the output was 681 thousand tonnes, and in 1999 24 million tonnes of aluminum were made. Also in 1999 some 7 million tonnes of recycled
aluminum were produced, giving 31 million tonnes in total. This is more than the production of all the non-ferrous metals combined, even though they were discovered hundreds of years earlier.
Summary: Aluminum is very reactive, and so it is difficult to extract, this meant discovery was prolonged until the 19th century (1800s). At first it was a very rare commodity, but as processes developed and prices dropped it became more widely available. Now it has one of the world's highest annual production levels.
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