ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Subconchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Al2SiO4(F,OH)2