Almandine

n. red colored mineral, almandite

Almandine, also known incorrectly as almandite, is a species of mineral belonging to the garnet Group. The name is a corruption of alabandicus, which is the name applied by Pliny the Elder to a stone found or worked at Alabanda, a town in Caria in Asia Minor. Almandine is an iron alumina garnet, of deep red color, inclining to purple. It is frequently cut with a convex face, or en cabochon, and is then known as carbuncle. Viewed through the spectroscope in a strong light, it generally shows three characteristic absorption bands. Almandine is one end-member of a mineral solid solution series, with the other end member being the garnet pyrope. The almandine crystal formula is: Fe3Al2(SiO4)3. Magnesium substitutes for the iron with increasingly pyrope-rich composition.
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Noun
1. a purple variety of the ruby spinel
(hypernym) spinel ruby, ruby spinel
2. a deep red garnet consisting of iron aluminum silicate
(synonym) almandite
(hypernym) garnet

n. almandine, red colored mineral, almandite

(n.)
The common red variety of garnet.