Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Uneven
(Cs,Na)(AlSi 2O 6) · 0.5H 2OWalter Schumann , Gemstones of the world (2001) More from other references
Fe3+ PO 4 · 2H 2OAnthony et al , Handbook of Mineralogy (2001)