sedimentary

Iron-stained weathered pebble

Likely ferruginous sandstone or iron-rich chert; exact identification requires testing

AI-generated identification · may be incorrect

Brown, dull to earthy luster, fine-grained and rounded, with dark reddish-brown iron-oxide spots or pits; likely hardness about 5–7 Mohs, no visible cleavage, and moderate-to-high density.

Identified August 22, 2026More sedimentary →

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Physical properties

Brown, dull to earthy luster, fine-grained and rounded, with dark reddish-brown iron-oxide spots or pits; likely hardness about 5–7 Mohs, no visible cleavage, and moderate-to-high density.

Formation & geological history

Probably a naturally weathered and water-rounded fragment formed from iron-rich sedimentary material; its geological age cannot be determined from the image. Surface cavities may reflect weathering of softer mineral grains or iron-oxide concentrations.

Uses & applications

Primarily a curiosity, teaching specimen, or decorative pebble; it has negligible industrial or jewelry use unless polished and visually distinctive.

Geological facts

The coloration is consistent with hematite/goethite staining, common products of oxidation in soils and groundwater. The apparent markings are natural pits or inclusions rather than diagnostic fossils.

Field identification & locations

Test streak on unglazed porcelain: hematite gives red-brown, while goethite gives yellow-brown; a glass-scratch test helps distinguish harder chert from softer sandstone. Common in stream gravels and iron-rich soils worldwide.