Crystal Yellow Topaz

Chemical Formula	Al2SiO4(F,OH)2
Color	White, Colorless, Blue, Red, Green, Yellow, Orange, Brown, Pink, Purple, Gray, Multicolored
Hardness	8
Crystal System	Orthorhombic
Refractive Index	1.610 - 1.638
SG	3.4 - 3.6
Transparency	Transparent
Double Refraction	.014
Luster	Vitreous
Cleavage	1,3 - basal
Mineral Class	Topaz