Chemical Classification

Silicate

Color

Quartz occurs in virtually every color. Common colors are clear, white, gray, purple, yellow, brown, black, pink, green, red.

Streak

Colorless (harder than the streak plate)

Luster

Vitreous

Diaphaneity

Transparent to translucent.

Cleavage

None - typically breaks with a conchoidal fracture

Mohs Hardness

7

Specific Gravity

2.6 to 2.7

Diagnostic Properties

Conchoidal fracture, glassy luster, hardness

Chemical Composition

SiO2

Crystal System

Hexagonal

Uses

Glass making, abrasive, foundry sand, hydraulic fracturing proppant, gemstones