metamorphic
Quartzite
Metamorphic Quartzite (SiO2)
Hardness of 7 on the Mohs scale; white, gray, pink, or reddish-brown color; vitreous to greasy luster; non-foliated, granular crystal structure; lacks distinct cleavage; specific gravity of 2.65.
Identified More metamorphic →
Explore Quartzite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 7 on the Mohs scale; white, gray, pink, or reddish-brown color; vitreous to greasy luster; non-foliated, granular crystal structure; lacks distinct cleavage; specific gravity of 2.65.
Formation & geological history
Formed through the metamorphism of quartz sandstone or chert under high heat and pressure, typically in mountain-building events over millions of years.
Uses & applications
Used in construction, railroad ballast, decorative aggregates, dimension stone, and the production of ferrosilicon and silicon.
Geological facts
Quartzite is extremely durable and resistant to chemical weathering, which is why ridges formed of quartzite often endure as prominent mountain crests.
Field identification & locations
Can be identified by its inability to be scratched by a knife, its lack of effervescence with acid, and its sugary, interlocking quartz grain texture on fractured surfaces.
More like this
