Crystal Smoky Quartz

Chemical Formula	SiO2
Color	Brown, Black
Hardness	7
Crystal System	Hexagonal
Refractive Index	1.54 - 1.55
SG	2.63 - 2.65
Transparency	Transparent to translucent
Double Refraction	.009
Luster	Vitreous
Cleavage	Indiscernible
Mineral Class	Quartz