sedimentary

Rounded gray pebble

Uncertain; likely quartz-rich sandstone, quartzite, or graywacke

AI-generated identification · may be incorrect

Fine-grained, smooth, and subrounded to rounded, with a dull gray surface; hardness is approximately 6–7 if quartz-rich, with no visible cleavage and low to moderate specific gravity. The image is too blurred for reliable mineral identification.

Identified August 13, 2026More sedimentary →

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Physical properties

Formation & geological history

Most likely weathered and water-rounded from a river, beach, or glacial deposit; the original rock may be sedimentary or metamorphosed sandstone. Its geological age cannot be determined visually.

Uses & applications

Commonly used as a landscaping, decorative, craft, or aquarium stone; little commercial or jewelry value unless it proves to be an unusual mineral or fossil.

Geological facts

Shape and surface indicate prolonged abrasion, which removes sharp edges and weak mineral grains. A streak, hardness, and close-up inspection would distinguish quartzite from softer sandstone or other gray rocks.

Field identification & locations

Look for visible sand grains, layering, quartz sparkle, carbonate fizz, or a colored streak; test hardness against glass and examine an unweathered surface. Rounded gray pebbles are common in stream gravels, beaches, and glacial tills worldwide.