igneous
Weathered granite or granitic gneiss
Granite; mainly quartz (SiO₂), feldspar, and mica; possible weak gneissic texture
AI-generated identification · may be incorrectCoarse, granular, pale gray-beige rock with visible quartz/feldspar and dark mica; typically Mohs 6–7, vitreous to dull luster, no consistent cleavage as a whole, and specific gravity about 2.6–2.7.
Identified More igneous →
Explore Weathered granite or granitic gneiss in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Coarse, granular, pale gray-beige rock with visible quartz/feldspar and dark mica; typically Mohs 6–7, vitreous to dull luster, no consistent cleavage as a whole, and specific gravity about 2.6–2.7.
Formation & geological history
Formed by slow cooling of silica-rich magma deep in the crust, generally during Precambrian to younger continental geological events; surface weathering has rounded and stained this specimen.
Uses & applications
Commonly used as crushed stone, aggregate, building stone, paving, monuments, and countertops; attractive pieces may be collected but this example has little gem value.
Geological facts
Granite is an intrusive igneous rock, while gneiss is its metamorphic counterpart; distinguishing them requires checking whether minerals form distinct light-dark banding.
Field identification & locations
Look for interlocking quartz and feldspar grains, scattered black mica, and hardness sufficient to scratch glass; common in continental mountain belts and glaciated terrains. A hand lens and fresh broken surface would improve identification.
