metamorphic

Quartzite (or Quartz)

SiO2 (Silicon Dioxide)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale. Color: Pale blue-grey, white, to light green. Luster: Vitreous to waxy. Crystal Structure: Trigonal. Specific Gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Pale blue-grey, white, to light green
Luster: Vitreous to waxy

Identified July 22, 2026More metamorphic →

Explore Quartzite (or Quartz) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 on Mohs scale. Color: Pale blue-grey, white, to light green. Luster: Vitreous to waxy. Crystal Structure: Trigonal. Specific Gravity: ~2.65.

Formation & geological history

Formed through the metamorphism of quartz-rich sandstone under intense heat and pressure, causing quartz grains to recrystallize into an interlocking mosaic.

Uses & applications

Used as decorative stone, crushed stone in road construction, building material, and as collector specimens.

Geological facts

Quartzite is extremely durable and resistant to chemical weathering, making it a prominent feature in mountainous terrain as resistant ridges.

Field identification & locations

Identified by its extreme hardness (scratches glass and steel easily) and sugary, interlocking crystalline texture. Commonly found in metamorphic belts worldwide.