Brittle, UnevenArthur Thomas, Gemstones (2009), Brittle, Uneven
Irregular/uneven, UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Uneven
(Mg,Fe)Al 3(BO 4)(SiO 4)OUlrich Henn and Claudio C.
CaAl 2Si 3O 10 · 3H 2OUlrich Henn and Claudio C.