Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Uneven, Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Uneven, Subconchoidal, Brittle, Metallic, Brittle, Metallic
Na 3(Na,K)Al 4Si 4O 16Ulrich Henn and Claudio C.
Zn 2(AsO 4)(OH)Michael OâDonoghue , Gems, Sixth edition (2006)