Uneven, Uneven, Gemstones of the world (2001) More from other references
Uneven, UnevenArthur Thomas, Gemstones (2009), Splintery
H 4Mg 3Si 2O 9Walter Schumann , Gemstones of the world (2001) More from other references
Ca 2(Mg,Fe) 5Si 8O 22(OH) 2Ulrich Henn and Claudio C.