Worlds of David Darling
Encyclopedia of Science
   
Home > Encyclopedia of Science

epidote




epidote
Orthosilicate mineral, hydrated calcium iron aluminum silicate (Ca2Fe3(Al2O)(OH)(Si2O7)[Si2O4]). It is found in metamorphic and igneous rocks as monoclinic system prismatic crystals and fibrous or granular masses; it is typically pistachio green, glassy, and brittle. Certain large crystals, 7.5–25cm (3–10in), are collector's items.

Hardness 6–7; relative density 3.4.


Related category

   • GEOLOGY AND PLANETARY SCIENCE