Source : Webster's Revised Unabridged Dictionary (1913)

Idocrase \Id"o*crase\ ([i^]d"[-o]*kr[=a]s; 277), n. [Gr. e'i^dos
   form + kra^sis mixture, fr. keranny`nai to mix; cf. F.
   idocrase.] (Min.)
   Same as {Vesuvianite}.

Source : WordNet®

idocrase
     n : 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}]