sedimentary

Iron-rich sandstone concretion

Ferruginous sandstone, cemented chiefly by iron oxides (such as goethite and hematite)

AI-generated identification · may be incorrect

Tan to ochre, rounded and granular with a dull, earthy luster; hardness and density vary with cementation. The image does not show enough detail to determine grain size or exact mineral composition.

Identified September 23, 2026More sedimentary →

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Physical properties

Tan to ochre, rounded and granular with a dull, earthy luster; hardness and density vary with cementation. The image does not show enough detail to determine grain size or exact mineral composition.

Formation & geological history

Likely formed as groundwater deposited iron-oxide cement among sand grains, producing a resistant rounded concretion. Such concretions form in sedimentary environments over geological time; the specimen’s age and locality cannot be determined from the image.

Uses & applications

Primarily a collecting or decorative specimen; iron-rich sandstone has limited industrial use compared with iron ore or construction-grade sandstone.

Geological facts

Iron-oxide concretions can weather out of softer surrounding rock and become rounded by erosion.

Field identification & locations

Look for visible sand grains, earthy texture, and rusty orange-brown coloration; a fresh broken surface would help distinguish sandstone from other iron-rich rocks. Similar material occurs in sedimentary basins worldwide.