Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Na 3(Na,K)Al 4Si 4O 16Ulrich Henn and Claudio C.
CaMoO 4Michael OâDonoghue , Gems, Sixth Edition (2006)