Uneven, Conchoidal, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
FeS 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
CaMoO 4Michael OâDonoghue , Gems, Sixth Edition (2006)