Cro*cid"o*lite (kr?-s?d"?-l?t), n. [Gr. kroky`s nap on cloth + -lite.] (Min.) A mineral occuring in silky fibers of a lavender blue color. It is related to hornblende and is essentially a silicate of iron and soda; -- called also blue asbestus. A silicified form, in which the fibers penetrating quartz are changed to oxide of iron, is the yellow brown tiger-eye of the jewelers.