Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Al 6B 5O 15(F,OH) 3Ulrich Henn and Claudio C.
3NaAlSi 3O 8 · NaClAnthony et al , Handbook of mineralogy (2001)