ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Be 3Al 2Si 6O 18Ulrich Henn and Claudio C.
Na 3(Na,K)Al 4Si 4O 16Ulrich Henn and Claudio C.