EXAMPLES | WORD ORIGIN noun the natural or synthetic oxide of aluminum, Al 2O 3, occurring in nature in a pure crystal form as corundum. Origin of alumina 1780–90;
alūmen alum 1
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for alumina Historical Examples of alumina
It is composed of silica,
alumina, carbonate of lime, magnesia and oxide of iron.
It usually contains a little silica,
alumina, and oxide of iron.
The affinity of
alumina for the colouring matter is very remarkable.
At the end of this time it must be washed, to extract the sulphate of
alumina may be separated from the ferric oxide by potash-lye. British Dictionary definitions for alumina Word Origin for alumina
C18: from New Latin, plural of Latin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Any of several forms of aluminum oxide used in aluminum production and in abrasives, refractories, ceramics, and electrical insulation. Alumina occurs naturally as the mineral corundum and, with minor traces of chromium and cobalt, as the minerals ruby and sapphire, respectively. In its hydrated form it also occurs as the rock bauxite. Also called aluminum oxide. Chemical formula: Al 2O 3.
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