Not Available, Southern and central Africa
Southern and central Africa
Green, Black, White, Grey, Green, Black, White, Grey, Green, Black, gray, Black, Green, Black, gray, Black
Colorless, Greenish, Colorless, Green, gray, Yellow
Uneven, UnevenArthur Thomas, Gemstones (2009), Splintery
Irregular/uneven, Uneven
Ca 2(Mg,Fe) 5Si 8O 22(OH) 2Ulrich Henn and Claudio C.
Ca 2Al 3(SiO 4) 3(OH)Walter Schumann , Gemstones of the world (2001) More from other references