Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Uneven
Uneven, UnevenArthur Thomas, Gemstones (2009)
ThCa 2Si 8O 20Walter Schumann , Gemstones of the world (2001) More from other references
KCa 4Si 8O 20(F,OH) · 8H 2OUlrich Henn and Claudio C.