igneous
Granite (likely biotite-bearing granite)
Granite, composed mainly of quartz, feldspar, and mica (likely biotite)
AI-generated identification · may be incorrectCoarse, speckled gray-brown rock with visible interlocking mineral grains. Typical granite hardness is about 6–7 Mohs; it has a granular texture and no consistent cleavage as a whole rock.
Identified More igneous →
Explore Granite (likely biotite-bearing granite) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Coarse, speckled gray-brown rock with visible interlocking mineral grains. Typical granite hardness is about 6–7 Mohs; it has a granular texture and no consistent cleavage as a whole rock.
Formation & geological history
Formed when silica-rich magma cooled slowly underground, allowing large crystals to grow. Granite bodies occur in continental crust and range widely in geological age.
Uses & applications
Commonly used as building and paving stone, countertops, monuments, and decorative aggregate; these small rough fragments have little commercial value.
Geological facts
The light grains are likely quartz and feldspar, while the darker flecks may be biotite or other mafic minerals.
Field identification & locations
Identify granite by its visible, interlocking light and dark grains and lack of layering. It is widespread in continental mountain belts and ancient crust; a hand sample alone cannot confirm the exact minerals.
