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Webster 1913 Edition
Idocrase
Id′o-crase
(ĭd′ō̍-krās; 277)
, Noun.
 [Gr. 
εἶδοσ 
form + κρᾶσισ 
mixture, from κεραννύναι 
to mix; cf. F. idocrase
.] (Min.) 
Same as 
Vesuvianite
. Webster 1828 Edition
Idocrase
ID'OCRASE
,Noun.
 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.