Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Uneven
PbCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Fe3+ PO 4 · 2H 2OAnthony et al , Handbook of Mineralogy (2001)