ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
ConchoidalArthur Thomas, Gemstones (2009)
Ca 5(F,Cl)(PO 4) 3Arthur Thomas , Gemstones (2009)
MnTa 2O 6Walter Schumann , Gemstones of the world (2001) More from other references