Brittle, Metallic, Brittle, Metallic
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Ca(VO)Si4O10•4(H2O)
KNa 2(Fe3+ ,Mn3+ ,Al) 2Li 3Si 12O 30Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references