Splintery, Granular, Splintery, Granular, Gemstones (2009)
Irregular/uneven, UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Uneven
Ca 2(Mg,Fe) 5(OH) 2Walter Schumann , Gemstones of the world (2001) More from other references
CaAl 2Si 3O 10 · 3H 2OUlrich Henn and Claudio C.