Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
PbCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
SbTaO 4Ulrich Henn and Claudio C.