almandine

views updated May 08 2018

almandine Member of the garnet group of minerals, Fe3Al2(SiO4)3; sp. gr. 4.25; hardness 6.5–7.5; cubic; red, brown-red, or black; greasy to vitreous lustre; most common crystals are dodecahedra, and many are irregular grains; widely distributed in metamorphic and igneous rocks, and in beach sands and placers. Transparent crystals are used as gemstones, and the mineral is useful in general as an abrasive.

almandine

views updated May 09 2018

almandine variety of garnet. XVII. — F. †almandine, alt. of †alabandine — late L. alabandīna (sc. gemma gem), f. Alabanda city of Caria; see -INE1.

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