ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001), Brittle, Metallic
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
BeAlSiO 4(OH)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
PbCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references