sedimentary

Rounded iron-rich pebble

Likely ferruginous sandstone or ironstone; exact identification requires testing

AI-generated identification · may be incorrect

Brown-red, dull to earthy luster, fine-grained and rounded, with possible dark iron-oxide spots. Estimated Mohs hardness 4–6; cleavage absent; specific gravity commonly 2.5–3.5.

Identified August 23, 2026More sedimentary →

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Physical properties

Brown-red, dull to earthy luster, fine-grained and rounded, with possible dark iron-oxide spots. Estimated Mohs hardness 4–6; cleavage absent; specific gravity commonly 2.5–3.5.

Formation & geological history

Likely weathered and water-rounded from an iron-bearing sedimentary outcrop or gravel deposit; age cannot be determined from the photograph. Iron oxides such as hematite or goethite produce the reddish coloration.

Uses & applications

Usually valued as a natural curiosity, landscaping gravel, or teaching specimen; it has little jewelry or industrial value unless unusually dense or mineralogically distinctive.

Geological facts

The smooth oval shape indicates transport by water or abrasion. A reddish-brown streak and attraction to a strong magnet would help distinguish ironstone from ordinary sandstone.

Field identification & locations

Common in stream gravels, road cuts, beaches, and weathered iron-rich formations worldwide. Test streak on unglazed ceramic, hardness against a steel nail, density, and magnetism; the image alone cannot confirm the rock type.