Southern and central Africa, Sixth Edition (2006)
USA, Zambia, Madagascar, India, Sri Lanka, Russia, Australia, Color: violet, purple-violet, Hardness: 7, Refractive index: 1.54 1.55, Density: 2.65 2.66, Chemical composition: SiO2, Crystal structure: hexagonal, Lustre: vitreous, Origins: Widespread; main sources are Brazil, Uruguay, Bolivia, Argentina, USA, East Africa, Zambia, Namibia, Madagascar, India, Sri Lanka, Russia, Brazil, Uruguay, Bolivia, Argentina, Australia, Brazil, Uruguay, Bolivia, Argentina, Australia
Blue, Green, Blue, Brown
Violet, White, Colorless, Blue, Red, Green, Yellow, pink, Violet, pink
Taurus
Pisces, Scorpio, Sagittarius, Pisces, Scorpio, Sagittarius, Pisces, Scorpio, Sagittarius
Sub-Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)