igneous
Rounded, mottled pebble (likely granitoid)
Probable granitic or dioritic rock; exact identification requires closer inspection
AI-generated identification · may be incorrectCoarse, irregular black, cream, and pale-green mineral grains in a rounded, weathered pebble. Likely quartz and feldspar with dark mica or amphibole; hardness and crystal structure cannot be reliably determined from the image.
Identified More igneous →
Explore Rounded, mottled pebble (likely granitoid) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Coarse, irregular black, cream, and pale-green mineral grains in a rounded, weathered pebble. Likely quartz and feldspar with dark mica or amphibole; hardness and crystal structure cannot be reliably determined from the image.
Formation & geological history
If granitoid, it crystallized slowly from magma deep in the crust, then was exposed and rounded by weathering and water transport. Its geological age cannot be determined visually.
Uses & applications
Primarily a natural collectible or landscaping pebble; granitoid stone is also widely used as dimension stone and aggregate.
Geological facts
The contrasting light and dark patches suggest a mixture of minerals rather than a single mineral crystal.
Field identification & locations
Look for interlocking grains and test suspected quartz for hardness (Mohs 7); the smooth, rounded shape is consistent with stream or shoreline abrasion. Granitoids occur worldwide.
