metamorphic
Quartzite
Quartzite (primarily SiO2)
Hardness: 7 on Mohs scale; Color: typically white, gray, or tan; Luster: vitreous to dull; Crystal structure: Non-foliated, granular; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7
- Hardness
- 7 on Mohs scale
- Color
- typically white, gray, or tan
- Luster
- vitreous to dull
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale; Color: typically white, gray, or tan; Luster: vitreous to dull; Crystal structure: Non-foliated, granular; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7
Formation & geological history
Formed through the metamorphism of quartz-rich sandstone subjected to high heat and pressure, typically during mountain-building events (orogeny). Often Precambrian to Paleozoic in age.
Uses & applications
Used as crushed stone for road construction, railroad ballast, and in the manufacturing of glass and ceramics. Polished varieties are used for countertops and flooring.
Geological facts
Quartzite is so hard that it will scratch glass and even high-quality steel. It is one of the most durable rocks on Earth's surface and often forms the resistant caps of ridges and mountains.
Field identification & locations
Identify in the field by its extreme hardness and grainy sand-like texture that unlike sandstone, breaks through the grains rather than around them. Commonly found in folded mountain belts globally.
More like this
