Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Uneven, Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Uneven, Subconchoidal, Brittle, Metallic, Brittle, Metallic
Na 8Al 6Si 6O 24(SO 4) · H 2OAnthony et al , Handbook of Mineralogy (2001)
Zn 2(AsO 4)(OH)Michael OâDonoghue , Gems, Sixth edition (2006)