ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Al 2Be 3Si 6O 18Martin H.
3CaAl 2Si 2O 8 · CaCO 3Anthony et al , Handbook of mineralogy (2001)