Number 19

Color--------------------Clear

Luster------------------Nonmetallic, glassy to shiny

Streak------------------None - White (harder than streak plate)

Hardness--------------7.0

Cleavage/--------------Fracture, jagged
Fracture

S.G.---------------------2.65

Special Properties---Hardest common mineral known to man.

Formula----------------SiO2

Mineral name---------Rock crystal quartz

Family------------------Silicates

Uses--------------------Glass making

Rock Crystal Quartz