metamorphic
Quartzite
Metamorphic Quartzite
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, color typically ranges from white and grey to pink or reddish-brown due to iron oxide impurities, vitreous to greasy luster, non-foliated massive crystal structure, conchoidal fracture, specific gravity around 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 typically ranges from white and grey to pink or reddish-brown due to iron oxide impurities, vitreous to greasy luster, non-foliated massive crystal structure, conchoidal fracture, specific gravity around 2.65.
Formation & geological history
Formed from quartz-rich sandstone or chert through the processes of regional or contact metamorphism, where intense heat and pressure cause quartz grains to recrystallize and interlock.
Uses & applications
Used in construction, as crushed stone for roadbeds, railway ballast, building facades, decorative landscaping, and occasionally for countertops and ornamental carvings.
Geological facts
Quartzite is extremely durable and weather-resistant, which is why quartz-rich sandstones often transform into exceptionally tough mountain ridges as the surrounding softer rocks erode away.
Field identification & locations
Can be identified in the field by its extreme hardness (it will easily scratch glass and cannot be scratched by a steel knife) and the fact that it breaks across the quartz grains rather than around them.
More like this
Other metamorphic specimens
Nephrite Jade
Nephrite
Mineral/Rock
Amphibolite
Amphibolite
metamorphic
Rhodonite
Manganese Silicate (Mn, Fe, Mg, Ca)SiO3
mineral
Rhodonite
(Mn,Fe,Mg,Ca)SiO3
mineral
Greenschist
Greenschist (containing Chlorite, Actinolite, and Epidote)
metamorphic
Garnet
Garnet group: X3Y2(SiO4)3 (commonly Almandine-Pyrope series)
mineral