Gems, Sixth Edition (2006), Gems, Sixth Edition (2006)
Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Metallic
SiO 2Michael OâDonoghue , Gems, Sixth Edition (2006)
CuSMichael OâDonoghue , Gems, Sixth edition (2006) More from other references