Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Subconchoidal, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
3NaAlSi 3O 8 · NaClAnthony et al , Handbook of mineralogy (2001)
TiO 2Michael OâDonoghue , Gems, Sixth edition (2006) More from other references