Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
3NaAlSi 3O 8 · NaClAnthony et al , Handbook of mineralogy (2001)
(Mg,Fe2+ )Al 2O 4Gemdat.org , Management Team (2012) More from other references