Black, Brownish, Brown, Black, Brownish
Colorless, Yellow, Blue, Reddish, Black, Reddish, Brown, Blue, gray, Black, Reddish, Brown, Blue, gray
Uneven
Subconchoidal, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
None, parting may develop along {111}
Perfect on [001] and [011]