sedimentary

Iron-rich concretion or weathered ironstone

Goethite–hematite limonite aggregate (FeO(OH), Fe₂O₃, and hydrated iron oxides)

AI-generated identification · may be incorrect

Dark brown to black, reddish weathering surfaces, earthy to submetallic luster, and irregular botryoidal texture; typically opaque, hardness about 4–6, with no obvious cleavage. The image alone cannot confirm whether it is an ironstone, slag, or meteorite.

Identified August 25, 2026More sedimentary →

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At a glance

Common name: Iron-rich concretion or weathered ironstone
Scientific name: Goethite–hematite limonite aggregate (FeO(OH), Fe₂O₃, and hydrated iron oxides)
Category: sedimentary
Identified: August 25, 2026
Method: Standard

AI Estimated Value

$1–$20 as a common ironstone specimen; potentially more if laboratory-confirmed as an unusual meteorite, but the image does not support that conclusion.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Likely formed by groundwater precipitation and weathering that concentrated iron oxides in sediment, commonly during the Cenozoic or older weathering cycles. Its rounded shape may reflect stream transport; a meteorite identification would require density, magnetic, and laboratory tests.

Uses & applications

Common ironstone has limited collector value and historically served as iron ore or pigment; it is not normally used as a gemstone or construction stone.

Geological facts

A strong magnet, unusually high density, and a thin fusion crust could suggest meteorite, but rust-colored iron oxides and porous, pitted surfaces more commonly indicate terrestrial ironstone. Metallic streaks or glassy vesicles may instead indicate industrial slag.

Field identification & locations

Common in lateritic soils, river gravels, coastal gravels, and iron-rich sedimentary formations worldwide. Check streak (hematite red-brown; magnetite black), magnetism, heft, and for visible quartz or vesicles; definitive identification needs testing.