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Before the Hall-Héroult process was developed, aluminium was exceedingly difficult to extract from its various ores. This made pure aluminium more valuable than gold[citation needed]. Bars of aluminium were exhibited alongside the French crown jewels at the Exposition Universelle of 1855[citation needed], and Napoleon III was said[citation needed] to have reserved a set of aluminium dinner plates for his most honoured guests. Aluminium was selected as the material to be used for the apex of the Washington Monument in 1884, a time when one ounce (30 grams) cost the daily wage of a common worker on the project;[38] aluminium was about the same value as silver. The Cowles companies supplied aluminium alloy in quantity in the United States and England using smelters like the furnace

of Carl Wilhelm Siemens by 1886.[39] Charles Martin Hall of Ohio in the U.S. and Paul Héroult of France independently developed the Hall-Héroult electrolytic process that made extracting aluminium from minerals cheaper and is now the principal method used worldwide. The Hall-Heroult process cannot produce Super Purity Aluminium directly. Hall's process,[40] in 1888 with the financial backing of Alfred E. Hunt, started the Pittsburgh Reduction Company today known as Alcoa. Héroult's process was in production by 1889 in Switzerland at Aluminium Industrie, now Alcan, and at British Aluminium, now Luxfer Group and Alcoa, by 1896 in Scotland.[41] By 1895 the metal was being used as a building material as far away as Sydney, Australia in the dome of the Chief Secretary's Building.

Many navies use an aluminium superstructure for their vessels, however, the 1975 fire aboard USS Belknap that gutted her aluminium superstructure, as well as observation of battle damage to British ships during the Falklands War, led to many navies switching to all steel superstructures. The Arleigh Burke class was the first such U.S. ship, being constructed entirely of steel. In 2008 the price of aluminium peaked at $1.45/lb in July but dropped to $0.7/lb by December.[42] 10. Etymology 10.1 Nomenclature history The earliest citation given in the Oxford English Dictionary for any word used as a name for this element is alumium, which British chemist and inventor Humphry Davy employed in 1808 for the metal he was trying to isolate electrolytically from the mineral alumina. The

citation is from his journal Philosophical Transactions: "Had I been so fortunate as..to have procured the metallic substances I was in search of, I should have proposed for them the names of silicium, alumium, zirconium, and glucium."[43] By 1812, Davy had settled on aluminum. He wrote in the journal Chemical Philosophy: "As yet Aluminum has not been obtained in a perfectly free state."[44] But the same year, an anonymous contributor to the Quarterly Review, a British political-literary journal, objected to aluminum and proposed the name aluminium, "for so we shall take the liberty of writing the word, in preference to aluminum, which has a less classical sound."[45] The -ium suffix had the advantage of conforming to the precedent set in other newly

discovered elements of the time: potassium, sodium, magnesium, calcium, and strontium (all of which Davy had isolated himself). Nevertheless, -um spellings for elements were not unknown at the time, as for example platinum, known to Europeans since the sixteenth century, molybdenum, discovered in 1778, and tantalum, discovered in 1802. The -um suffix on the other hand, has the advantage of being more consistent with the universal spelling alumina for the oxide, as lanthana is the oxide of lanthanum, and magnesia, ceria, and thoria are the oxides of magnesium, cerium, and thorium respectively. The spelling used throughout the 19th century by most U.S. chemists ended in -ium, but common usage is less clear.[46] The -um spelling is used in the Webster's Dictionary of 1828, as it was

in 1892 when Charles Martin Hall published an advertising handbill for his new electrolytic method of producing the metal, despite his constant use of the -ium spelling in all the patents[40] he filed between 1886 and 1903.[47] It has consequently been suggested that the spelling reflects an easier to pronounce word with one fewer syllable, or that the spelling on the flier was a mistake. Hall's domination of production of the metal ensured that the spelling aluminum became the standard in North America; the Webster Unabridged Dictionary of 1913, though, continued to use the -ium version. In 1926, the American Chemical Society officially decided to use aluminum in its publications; American dictionaries typically label the spelling aluminium as a British variant. 10.2 Present-day