ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Uneven, Uneven, Gems, Sixth Edition (2006)
Al 4(Ta,Nb) 3(O,OH,F) 14Ulrich Henn and Claudio C.
Al 2O 3Michael OâDonoghue , Gems, Sixth Edition (2006)