Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Uneven, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
LiAl(PO 4)(OH,F)Walter Schumann , Gemstones of the world (2001) More from other references
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