Uneven, Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Uneven, Subconchoidal, Brittle, Metallic, Brittle, Metallic
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle
Zn 2(AsO 4)(OH)Michael OâDonoghue , Gems, Sixth edition (2006)
Na 2(Ti,Fe)Si 4(O,F) 11Ulrich Henn and Claudio C.