Grey, Brown, Green, Colorless, White
White, Pale pink, Colorless, pink, Yellow
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Not Available
Ca 2Mg 5Si 8O 22(OH) 2Ulrich Henn and Claudio C.
Mn2+ BO 2(OH)Anthony et al , Handbook of mineralogy (2001)