Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Uneven
Na 3(Na,K)Al 4Si 4O 16Ulrich Henn and Claudio C.
Mn 3B 7O 13ClMichael OâDonoghue , Gems, Sixth Edition (2006)