Uneven, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
Subconchoidal, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
Na 4AlBeSi 4O 12ClMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
TiO 2Michael OâDonoghue , Gems, Sixth edition (2006) More from other references