alumina

American  

[uh-loo-muh-nuh] / əˈlu mə nə /

noun

1. the natural or synthetic oxide of aluminum, Al 2 O 3 , occurring in nature in a pure crystal form as corundum.

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alumina British  

/ əˈluːmɪnə /

noun

1. another name for aluminium oxide

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alumina Scientific  

/ ə-lo̅o̅′mə-nə /

1. 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 ₂ O ₃ .

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Etymology

Origin of alumina

1780–90; < Latin alūmin-, stem of alūmen alum ¹ + -a ⁴

Compare meaning

How does alumina compare to similar and commonly confused words? Explore the most common comparisons:

• alumina vs. aluminum

Example Sentences

Ionic MT said it discovered high grades of 16 different types of minerals, everything from lithium to alumina, germanium, rubidium, cesium, vanadium and niobium at the site in Utah’s Silicon Ridge.

From The Wall Street Journal

The company’s outlook may remain positive, supported by firm aluminum prices and easing alumina costs as supply expands.

From The Wall Street Journal

Proposed alternatives include minerals such as calcium carbonate, alpha alumina, rutile and anatase titania, cubic zirconia, and even diamond.

From Science Daily

The ore’s refined intermediate product—alumina—must go through electrolysis at a smelter to break aluminum’s strong bond to oxygen.

From The Wall Street Journal

Thanks to a A$400m federal loan, it is building one of the world’s largest alumina refineries near the coastal city of Gladstone, which it says will create hundreds of local jobs.

From BBC