Emily Dickinson Lexicon

ID'O-CRASE, n. [Gr. ιδεα, form, and κρασις, mixture; a mixed figure.]

A mineral, the vesuvian of Werner, sometimes massive, and very often in shining prismatic crystals. Its primitive form is a four-sided prism with square bases. It is found near Vesuvius, in unaltered rocks ejected by the volcano; also in primitive rocks in various other localities. Cleaveland.