UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, Brittle, Metallic
Gems, Sixth Edition (2006), Gems, Sixth Edition (2006)
CoAsSAnthony et al , Handbook of mineralogy (2001)
SiO 2Michael OâDonoghue , Gems, Sixth Edition (2006)