Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Uneven
ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
ThCa 2Si 8O 20Walter Schumann , Gemstones of the world (2001) More from other references
Al 2(Cl 2O 12) · 18H 2OUlrich Henn and Claudio C.