Blue, Yellow, Brown, gray, Reddish, Greenish
Blue, Red, Yellow, Colorless, Blue, Colorless, Green, Yellow, White, Blue, Colorless, Green, Yellow, White
(e.g. graphite).
Uneven, Conchoidal, Brittle, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
{???} Imperfect, {???} Imperfect
Poor/indistinct on {1120} and {1011}