Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Mg 2Al 4Si 5O 18Ulrich Henn and Claudio C.
3CaAl 2Si 2O 8 · CaCO 3Anthony et al , Handbook of mineralogy (2001)