White, Yellow, Blue, Green, Green, gray, Yellow
Colorless, Blue, Violet, White, Brown, Colorless, Blue, Violet, White, rose, Brown, gray, Colorless, White, Violet, gray, Colorless, White, Violet, gray
Uneven, Uneven, Gems
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
{001} Perfect, {010} Good
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.
KAlSi 3O 8Arthur Thomas , Gemstones (2009)
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references