sedimentary

Rounded quartz-rich pebble

Quartz-bearing lithic clast; exact rock type indeterminate from image

AI-generated identification · may be incorrect

Gray, fine-grained, subrounded pebble with a lighter vein or band and a dull-to-satin luster. Likely hardness about 6–7 Mohs if quartz-rich; no obvious cleavage, and specific gravity roughly 2.6–2.7.

Identified August 26, 2026More sedimentary →

Explore Rounded quartz-rich pebble in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Probably formed as a fragment of quartzite, siliceous sandstone, or fine-grained metamorphic rock, later transported and naturally rounded by water or abrasion. Its precise geological age and source cannot be determined visually.

Uses & applications

Primarily a collecting or decorative stone; comparable quartz-rich pebbles may be used in landscaping, aggregate, crafts, and polished-stone products.

Geological facts

The pale band may be quartz vein material, but it could also be a contrasting mineral layer or weathering feature. A glassy scratch test and lack of reaction with dilute hydrochloric acid would support a quartz-rich identification.

Field identification & locations

Common in streambeds, beaches, glacial deposits, and gravel bars worldwide. Test whether it scratches glass, inspect fresh surfaces with a loupe, and use a streak test; exact identification requires petrographic or chemical analysis.