UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Uneven, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Metallic
Na 8Al 6Si 6O 24Cl 2Michael OâDonoghue , Gems, Sixth Edition (2006)
KCa 2AlBe 2Si 12O 30 · 0.5H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references