igneous
Polished granite pebble
Granite (quartz–feldspar–biotite or amphibole-bearing granitoid; exact variety uncertain)
AI-generated identification · may be incorrectCoarse-grained, mottled gray, cream, and dark green-black; minerals have mostly vitreous to dull luster. Typical granite hardness is about 6–7 Mohs, with interlocking quartz and feldspar crystals and no prominent cleavage in the whole rock.
Identified More igneous →
Explore Polished granite pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Coarse-grained, mottled gray, cream, and dark green-black; minerals have mostly vitreous to dull luster. Typical granite hardness is about 6–7 Mohs, with interlocking quartz and feldspar crystals and no prominent cleavage in the whole rock.
Formation & geological history
Formed when silica-rich magma cooled slowly deep in the crust, likely millions to billions of years ago; the pebble was later rounded by transport and polished. Exact age and source cannot be determined from the image.
Uses & applications
Granite is widely used for building stone, countertops, paving, and decorative aggregates; this small polished specimen is mainly decorative or collectible.
Geological facts
Granite commonly contains quartz, feldspar, and dark mica or amphibole; its visible grains record slow underground cooling.
Field identification & locations
Look for interlocking light quartz/feldspar grains with scattered dark minerals and no layering. Similar pebbles occur in river and beach gravels worldwide; the image alone cannot confirm the precise rock variety.
