ConchoidalWalter Schumann, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Metallic
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Perfect on {010}, good on {100}
{???} Distinct, {???} Indistinct
Be 2BO 3(OH)Ulrich Henn and Claudio C.
3CaAl 2Si 2O 8 · CaCO 3Anthony et al , Handbook of mineralogy (2001)