metamorphic
Quartzite
Quartzite (Metamorphic Quartz Arenite)
Hardness of 7 on the Mohs scale, color ranges from white and grey to yellow, orange, and pink due to iron oxide impurities, vitreous to greasy luster, massive to granular crystal structure, conchoidal fracture, 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, color ranges from white and grey to yellow, orange, and pink due to iron oxide impurities, vitreous to greasy luster, massive to granular crystal structure, conchoidal fracture, specific gravity of 2.65.
Formation & geological history
Formed when quartz-rich sandstone or chert is subjected to high heat and pressure, typically through tectonic compression in orogenic belts. Geological age varies widely depending on the formation site, ranging from Precambrian to Cenozoic.
Uses & applications
Used in construction, railway ballast, road aggregate, manufacturing of silica brick, and occasionally as an ornamental stone or in countertops.
Geological facts
Pure quartzite is one of the most chemically inert and physically durable rocks on Earth, making it extremely resistant to weathering and erosion.
Field identification & locations
Identified by its high hardness (scratches glass easily), inability to be scratched by a steel knife, and the way it breaks across rather than around the quartz grains. Found worldwide in mountainous regions and ancient cratons.
More like this
