ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009)
Na 2Ca 2(CO 3) 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Fe,Mn)Ta 2O 6Walter Schumann , Gemstones of the world (2001) More from other references