Not Available
Russia, Brazil, Tanzania, Madagascar, Zambia, Sri Lanka, Burma, India, Color: color change, from bluish green (daylight) to purple, red or brown (incandescent light), Hardness: 8, Refractive index: 1.74 1.77, Density: 3.68 3.80, Chemical composition: BeAl2O4, Crystal structure: orthorhombic, Origins: Russia, Brazil, Tanzania, Madagascar, Zambia, Sri Lanka, Burma
Blue, White, Grey, Yellow, Green, Colorless, Red, gray
Green
(Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2
BeAl 2 O 4