Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Uneven, Uneven, Gems, Difficult, Fibrous
{???} Distinct, {???} Indistinct
None – parting in 3 directions
3CaAl 2Si 2O 8 · CaCO 3Anthony et al , Handbook of mineralogy (2001)
Al 2O 3Arthur Thomas , Gemstones (2009)