sedimentary

Concretion or weathered iron-rich rock

Likely limonite/goethite-rich concretion; exact identification requires testing

AI-generated identification · may be incorrect

Small rounded brown object with a dull, earthy granular surface; likely low-to-moderate hardness (about 3–5 Mohs), opaque, nonmetallic, and possibly weakly magnetic if iron-rich. No visible crystals or cleavage.

Identified August 24, 2026More sedimentary →

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Physical properties

Formation & geological history

Probably formed by cementation and concentration of iron oxides around a nucleus in sediment, or by weathering of an iron-bearing rock; age cannot be determined from the image.

Uses & applications

Primarily a curiosity or educational specimen; iron-rich material may have limited pigment or mineral-collecting interest, but it has no significant construction or jewelry use.

Geological facts

The spherical shape may represent a concretion, but similar appearances can result from naturally rounded weathering or industrial iron-bearing pellets.

Field identification & locations

Check for a rusty streak, magnetic response, density, and reaction to dilute hydrochloric acid; a uniformly porous, lightweight sphere could instead be a non-geological manufactured pellet. Common in sedimentary basins and weathering zones worldwide.