Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
TiO 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Mg 3(Al,Cr) 2(SiO 4) 3Gemdat.org , Management Team (2012)