igneous
Rounded river pebble, likely quartz-rich sandstone or fine-grained granite
Indeterminate from photograph; possible quartz/feldspar-bearing granitic pebble
AI-generated identification · may be incorrectSmall, water-worn, gray-brown specimen with a dull earthy luster and possible dark mineral flecks. Hardness is likely about 6–7 Mohs if quartz-rich; crystal structure and cleavage cannot be confirmed visually.
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Physical properties
Small, water-worn, gray-brown specimen with a dull earthy luster and possible dark mineral flecks. Hardness is likely about 6–7 Mohs if quartz-rich; crystal structure and cleavage cannot be confirmed visually.
Formation & geological history
Likely formed as part of an older continental igneous or sedimentary rock, then eroded and rounded by moving water; its geological age is undetermined. The smooth shape indicates transport in a river, beach, or gravel deposit.
Uses & applications
Primarily a curiosity or craft/collecting specimen; no significant commercial value at this size. Similar material may be used as aggregate, landscaping stone, or decorative pebble.
Geological facts
The image does not show diagnostic crystals, layering, fossils, or distinctive color patterns, so a precise identification is not reliable from appearance alone.
Field identification & locations
Test hardness against glass, inspect a fresh surface with a loupe, and apply dilute hydrochloric acid to check for carbonate fizz. Commonly found in stream gravel, beaches, landscaping aggregate, and glacial deposits.
