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alumina

noun

alu·​mi·​na ə-ˈlü-mə-nə How to pronounce alumina (audio)
: the oxide of aluminum Al2O3 that occurs both in pure form as corundum and in hydrated forms (as in bauxite)

Example Sentences

Recent Examples on the Web Producers refine an oxide from bauxite to create alumina, which is turned into aluminum metal at smelters. Micah Maidenberg, WSJ, 15 Jan. 2020 Prices of alumina, which is extracted from bauxite, rose until 2018, reviving the mining industry. The Economist, 9 Nov. 2019 Despite business-friendly rules, the recovery of foreign investment has been modest and, after a recent decline in alumina prices, may now falter. The Economist, 9 Nov. 2019 Last year, there was as deficit of alumina, according to the company. Micah Maidenberg, WSJ, 16 Jan. 2019 As Century paid a lot more for alumina, its profit margins were crushed even as aluminum prices surged. Peter Eavis, New York Times, 10 July 2019 Authorities in Brazil ordered a huge alumina producer to operate at half capacity after a spill. Peter Eavis, New York Times, 10 July 2019 Guinea is a hotbed of mining activity in recent months as aluminum firms from the U.S., China and Russia, try to carve out a piece of its massive bauxite-ore deposits used to produce alumina and aluminum. Costas Paris, WSJ, 2 Nov. 2018 Raw materials including coke, which helps to fuel iron-ore smelters, and caustic soda, used to extract alumina from bauxite, are also rocketing higher in price. Rhiannon Hoyle, WSJ, 12 Mar. 2018 See More

Word History

Etymology

New Latin, from Latin alumin-, alumen alum

First Known Use

circa 1790, in the meaning defined above

Time Traveler
The first known use of alumina was circa 1790

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