Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle
Not Available
(Cs,Na)(AlSi 2O 6) · 0.5H 2OWalter Schumann , Gemstones of the world (2001) More from other references
Ca 2(Mg,Fe,Mn,Al) 2(SiO 4)(Si 2O 7)(OH) 2 · H 2OUlrich Henn and Claudio C.