sedimentary

Likely ironstone or iron-oxide–stained pebble

Iron-rich concretion, probably goethite/limonite (FeO(OH)·nH₂O) coating a rock fragment

AI-generated identification · may be incorrect

Small rounded pebble with a golden-brown, earthy to slightly metallic surface and a pale gray-brown rim. Hardness and crystal structure cannot be determined reliably from the image; iron oxides commonly have Mohs hardness about 4–6 and no obvious cleavage.

Identified October 15, 2026More sedimentary →

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Physical properties

Formation & geological history

Iron oxides precipitate or accumulate around grains and fragments during weathering or sedimentary diagenesis; age and exact formation setting are unknown.

Uses & applications

Commonly collected as a curiosity; iron-rich material has historically been used as iron ore and pigment, but this tiny specimen has no practical industrial value.

Geological facts

The bright gold-like color is not enough to identify native gold; iron-oxide staining and weathering commonly create similar appearances.

Field identification & locations

Look for a rusty streak, earthy texture, and relatively high density; a streak test and examination of a fresh surface would help distinguish ironstone from metal or other minerals. Iron-rich pebbles occur in many sedimentary and weathered environments.