Rock Identifier
Rounded reddish-brown pebble (Likely ferruginous sandstone or iron-rich quartzite; exact identification requires a fresh surface and tests) — sedimentary
sedimentary

Rounded reddish-brown pebble

Likely ferruginous sandstone or iron-rich quartzite; exact identification requires a fresh surface and tests

AI-generated identification · may be incorrect

Fine-grained, matte to weakly earthy luster, reddish-brown from iron oxides, and smoothly water-rounded; likely hardness about 5–7 Mohs with no visible cleavage. The uniform texture suggests sandstone or quartzite rather than a crystal-rich igneous rock.

Identified More sedimentary
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Physical properties

Fine-grained, matte to weakly earthy luster, reddish-brown from iron oxides, and smoothly water-rounded; likely hardness about 5–7 Mohs with no visible cleavage. The uniform texture suggests sandstone or quartzite rather than a crystal-rich igneous rock.

Formation & geological history

Probably formed from quartz-rich sediment cemented into sandstone, possibly metamorphosed into quartzite, then weathered and rounded in a river, beach, or glacial setting. Its geological age cannot be determined from the photograph.

Uses & applications

Common material has little industrial or jewelry value, though attractive pebbles may be used in landscaping, décor, lapidary work, or educational collections.

Geological facts

Iron minerals such as hematite and goethite commonly produce red, brown, or purple coloration. The broad, smooth shape indicates prolonged abrasion during transport.

Field identification & locations

Check for gritty grains and fizz-free behavior: sandstone feels slightly sandy, while quartzite is exceptionally hard and rings when tapped. A steel file or glass-scratch test, streak test, and fresh broken surface would distinguish it more reliably; common worldwide.