idocrase n 1: a green or yellow or brown mineral consisting of a hydrated silicate; it occurs as crystals in limestone and is used a gemstone [syn: {vesuvianite}, {vesuvian}, {idocrase}]
Idocrase \Id"o*crase\ ([i^]d"[-o]*kr[=a]s; 277), n. [Gr. e'i^dos form + kra^sis mixture, from keranny`nai to mix; cf. F. idocrase.] (Min.) Same as {Vesuvianite}. [1913 Webster]
Vesuvianite \Ve*su"vi*an*ite\, n. (Min.) A mineral occurring in tetragonal crystals, and also massive, of a brown to green color, rarely sulphur yellow and blue. It is a silicate of alumina and lime with some iron magnesia, and is common at Vesuvius. Also called {idocrase}. [1913 Webster]