Brittle, Metallic, Brittle, Metallic
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Be 4Si 2O 7(OH) 2Anthony et al , Handbook of mineralogy (2001)
CaMoO 4Michael OâDonoghue , Gems, Sixth Edition (2006)