Conchoidal, Brittle, Conchoidal, Brittle, Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
PbSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
PbCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references