Australia, Italy
Tanzania, Madagascar, Kenya, Sri Lanka, Burma, Australia
Yellow, Red, Reddish, Brown, Colorless, White, Yellow, Red, Reddish, Brown, Colorless, White, gray, White, gray, Reddish, White, gray, Reddish, White, gray, Reddish
Green, Brown, Colorless, Greenish, Yellow
Conchoidal, Uneven
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Uneven
KAl3(SO4)2(OH)6
Mg 3Al 6(Si,Al,B) 5O 21(OH)Walter Schumann , Gemstones of the world (2001) More from other references