UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Uneven, Conchoidal, UnevenArthur Thomas, Brittle
Na 8Al 6Si 6O 24Cl 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Fe2+ CO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references