sedimentary

Ironstone (iron-oxide-rich rock)

Ferruginous sandstone or ironstone; likely composed chiefly of goethite and/or limonite, with quartz and clay

AI-generated identification · may be incorrect

Brown to ochre, earthy to dull luster, granular texture, and irregular fractures; hardness is variable, roughly 4–7 Mohs depending on cement and mineral content. The photo does not show diagnostic crystals, so the exact rock and mineral proportions cannot be confirmed.

Identified October 4, 2026More sedimentary →

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At a glance

Common name: Ironstone (iron-oxide-rich rock)
Scientific name: Ferruginous sandstone or ironstone; likely composed chiefly of goethite and/or limonite, with quartz and clay
Category: sedimentary
Identified: October 4, 2026
Method: Standard

AI Estimated Value

About $1–$20 for a common hand-sized specimen; higher value would require unusual structure, locality, or verified ore quality.

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

Forms when iron oxides precipitate or accumulate and cement sediment, often in shallow-water or weathering environments. Its age cannot be determined from appearance alone.

Uses & applications

Iron-rich ores can be processed for iron; lower-grade ironstone is also used as decorative stone or collected as a specimen.

Geological facts

Yellow-brown coloration commonly comes from hydrated iron oxides such as goethite and limonite; darker brown patches may reflect concentrated iron minerals.

Field identification & locations

Look for a dense, rusty-brown surface and possible ochre streak; a reddish-yellow-brown streak and relatively high density support ironstone. It occurs widely in sedimentary basins and weathered iron-rich soils; testing or laboratory analysis is needed for a firm identification.