Colorless, Blue, Violet, White, Brown, Colorless, Blue, Violet, White, rose, Brown, gray, Colorless, White, Violet, gray, Colorless, White, Violet, gray
Colorless, White, Blue, Yellow, Grey, Brown, Colorless, White, Blue, Yellow, Grey, Brown
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Irregular/uneven
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.
Perfect cleavage parallel to base and prism faces: {001} Perfect, {210} Perfect, {010} Imperfect