[ bal-uh s ]
/ ˈbæl əs /

noun (used with a singular verb) Mineralogy.

a spherical aggregate of small diamond crystals used for drilling and for various industrial purposes.

Origin of ballas

apparently variant of balas in phrase balas ruby spinel ruby, balas being taken to mean “spinel” Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

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