sedimentary

Ironstone / limonitic iron-rich rock

Goethite–hematite–limonite aggregate, commonly an ironstone concretion

AI-generated identification · may be incorrect

Rusty brown to dark gray, earthy to dull luster, porous and heavily weathered; likely Mohs hardness about 4–6, with no obvious cleavage. High density relative to ordinary sandstone and may leave a yellow-brown streak; magnetism varies with magnetite content.

Identified September 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Likely formed by oxidation and cementation of iron-bearing sediments or groundwater deposits, producing goethite, hematite, and hydrated iron oxides. The photograph cannot establish a precise geological age; such ironstone can form from ancient sedimentary deposits through relatively recent weathering.

Uses & applications

Mostly a collecting specimen or field curiosity; ironstone has historically been an iron ore, and durable varieties may be used as aggregate or building stone. This specimen does not appear gem-quality.

Geological facts

The porous, knobbly texture and orange-brown weathering rind are typical of iron-oxide concretions or weathered ironstone rather than a clean metallic meteorite. A streak test and magnet test would substantially improve identification.

Field identification & locations

Iron-rich concretions and weathered sandstone are plausible around the Kansas City region, where sedimentary rocks are widespread. Test an inconspicuous spot on unglazed porcelain: a yellow-brown to red streak supports limonite/goethite; strong attraction to a magnet suggests magnetite-bearing ironstone.