Number 20

Color--------------------Clear to colorless

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

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

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

Cleavage/--------------Fracture
Fracture

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

Special Properties---Hardest common mineral known to man. Second most abundant mineral of the crust.

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

Mineral name---------Milky Quartz

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

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

Milky Quartz