metamorphic
Quartzite
Metamorphic Quartz Arenite (SiO2)
Hardness of 7 on the Mohs scale, colors range from white and gray to pink, brown, and reddish due to iron oxide impurities. It typically has a vitreous to greasy luster, massive crystal structure with interlocking quartz grains, and lacks distinct cleavage.
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, colors range from white and gray to pink, brown, and reddish due to iron oxide impurities. It typically has a vitreous to greasy luster, massive crystal structure with interlocking quartz grains, and lacks distinct cleavage.
Formation & geological history
Formed from quartz-rich sandstone subjected to high heat and tectonic pressure during regional or contact metamorphism, fusing the quartz grains tightly together.
Uses & applications
Used in construction, road aggregate, manufacturing of silica bricks, wall tiles, and occasionally as a decorative stone or in landscaping.
Geological facts
Unlike sandstone, which breaks around the grains, quartzite fractures directly through the quartz grains because of the intense recrystallization during its formation.
Field identification & locations
Can be identified in the field by its extreme hardness (scratches glass easily), inability to be split along bedding planes, and sugary texture on freshly broken surfaces. Found worldwide in ancient mountain belts and cratons.
More like this
