CORUNDUM

Corundum

Corundum is a crystalline form of aluminium oxide with traces of iron, titanium and chromium. It is a rock-forming mineral. It is one of the naturally clear transparent materials, but can have different colors when impurities are present. Transparent specimens are used as gems, called ruby if red and padparadscha if pink-orange. All other colors are called sapphire, e.g., "green sapphire" for a green specimen.

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corundum

Noun

  1. An extremely hard mineral, a form of aluminum oxide with the chemical formula Al2O3, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive.


The above text is a snippet from Wiktionary: corundum
and as such is available under the Creative Commons Attribution/Share-Alike License.

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