Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Uneven, Conchoidal, UnevenArthur Thomas, Brittle
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
Fe2+ CO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references