metamorphic
Likely quartz-bearing metamorphic rock
Probably quartzite or quartz-rich schist; mainly quartz (SiO₂), possibly mica and feldspar
AI-generated identification · may be incorrectWhite to gray, granular, with darker gray mineral bands or inclusions; typically vitreous to dull luster and interlocking crystals. Quartz hardness is 7 Mohs; cleavage is absent, though the specimen may fracture irregularly. Exact identification is limited by the image.
Identified More metamorphic →
Explore Likely quartz-bearing metamorphic rock in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
White to gray, granular, with darker gray mineral bands or inclusions; typically vitreous to dull luster and interlocking crystals. Quartz hardness is 7 Mohs; cleavage is absent, though the specimen may fracture irregularly. Exact identification is limited by the image.
Formation & geological history
Likely formed when quartz-rich sandstone or a shale-like protolith was subjected to heat and pressure during regional metamorphism, generally over millions of years. Common in metamorphic belts and glacial or stream gravels.
Uses & applications
Quartzite is used as crushed stone, aggregate, building stone, and occasionally decorative material; attractive pieces may be collected but this specimen is not gem-grade.
Geological facts
Quartzite is highly resistant to weathering and commonly survives as rounded cobbles. If mica is abundant and the rock splits into thin sheets, it is more likely quartz-mica schist than quartzite.
Field identification & locations
Look for glassy quartz grains, strong resistance to scratching, and—if schistose—parallel flaky mica layers. Common sources include metamorphic mountain regions and transported river or beach gravels.
More like this
