Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
Uneven, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
Na 4AlBeSi 4O 12ClMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references