Scientific Name: Calcium aluminum iron silicate hydroxide
Group: Silicates – sorosilicates
Chemical composition: Ca2Al2(Fe,Al)(SiO4)(Si2O7)O(OH)
Colors: The color is green, grey, brown or nearly black, but usually a characteristic shade of yellowish-green or pistachio-green.
Hardness: 6 to 7
Formation: Monoclinic crystal
Principal Sources: Canada, France, Myanmar, Norway, Peru, Colorado and California.
Special Notes: Epidote is an abundant rock-forming mineral, but one of secondary origin. It occurs in marble and schistose rocks of metamorphic origin and is also a product of hydrothermal alteration of various minerals (feldspars, micas, pyroxenes, amphiboles, garnets, and others) composing igneous rocks. It occurs in regionally metamorphosed rocks as a product of hydrothermal alteration of plagioclase feldspar. Epidote is often found in conjunction with phrenite crystals.