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Aluminium (or aluminum in North American English) is a chemical element; it has symbol Al and atomic number 13. Aluminium has a density lower than that of other common metals, about one-third that of steel. It has a great affinity towards oxygen, forming a protective layer of oxide on the surface when exposed to air.
Prices for aluminium declined, and by the early 1890s, the metal had become widely used in jewelry, eyeglass frames, optical instruments, and many everyday items. Aluminium cookware began to be produced in the late 19th century and gradually supplanted copper and cast iron cookware in the first decades of the 20th century.
Welded aluminium alloy bicycle frame, made in the 1990s. An aluminium alloy (UK/IUPAC) or aluminum alloy (NA; see spelling differences) is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin, nickel and zinc.
Chapter 1. The History of Aluminium Before the 19th Century. Historical background of aluminium in ancient times; archeological findings containing aluminium; first historic mentions of aluminium articles; information about 'alum' – compound substances with chemical structures containing aluminium; production technologies alum and areas of their application in the Ancient Times and Middle Ages.
Charles Martin Hall (December 6, 1863 – December 27, 1914) was an American inventor, businessman, and chemist.He is best known for his invention in 1886 of an inexpensive method for producing aluminum, which became the first metal to attain widespread use since the prehistoric discovery of iron.
A metamorphic rock called emery that is mostly made of corundum which is an aluminum oxide. This is an example of an aluminum deposit. Aluminum is the third most abundant element in the lithosphere at 82,000 ppm. It occurs in low levels, 0.9 ppm, in humans. [1] Aluminum is known to be an ecotoxicant and expected to be a health risk to people.
Aluminium isotopes have found practical application in dating marine sediments, manganese nodules, glacial ice, quartz in rock exposures, and meteorites. The ratio of 26 Al to 10 Be has been used to study the role of sediment transport , deposition , and storage, as well as burial times, and erosion, on 10 5 to 10 6 year time scales.
The gibbsite is usually converted into aluminium oxide, Al 2 O 3, by heating in rotary kilns or fluid flash calciners to a temperature in excess of 1,000 °C (1,830 °F). This aluminium oxide is dissolved at a temperature of about 960 °C (1,760 °F) in molten cryolite .