Green, Green, Yellow, Brown, White, gray, Black
White, Colorless, Blue, Red, Green, Yellow, Violet
Splintery, Granular, Splintery, Granular, Gemstones (2009)
Not Available
Ca 2(Mg,Fe) 5(OH) 2Walter Schumann , Gemstones of the world (2001) More from other references
SiO 2Ulrich Henn and Claudio C.