UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
{110} Perfect, {110} Perfect
{???} Distinct, {???} Indistinct
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.
3CaAl 2Si 2O 8 · CaCO 3Anthony et al , Handbook of mineralogy (2001)