Uneven, Conchoidal, UnevenArthur Thomas, Brittle
Uneven, Conchoidal, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle
Fe2+ CO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
FeS 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references