mineral

Weathered iron-rich mineral concretion

Likely limonite/goethite concretion (hydrated iron oxides), possibly a weathered ironstone fragment

AI-generated identification · may be incorrect

Dark brown to bluish-gray, earthy to dull luster, irregular rounded form, and likely moderate density; hardness approximately 4–5.5 Mohs, with no visible crystal faces or cleavage. The blue-gray surface may reflect weathering, staining, or minor manganese minerals.

Identified August 16, 2026More mineral →

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At a glance

Common name: Weathered iron-rich mineral concretion
Scientific name: Likely limonite/goethite concretion (hydrated iron oxides), possibly a weathered ironstone fragment
Category: mineral
Identified: August 16, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 as an unverified common specimen; potentially $10–$30 if confirmed as an attractive, unusual locality specimen.

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

Formed when dissolved iron precipitated and cemented sediment or soil into a concretion, commonly during groundwater weathering; exact age cannot be determined from the photograph. Such specimens occur in soils, stream gravels, and sedimentary formations.

Uses & applications

Primarily a collecting or educational specimen; iron oxides are important ores and pigments, but this small piece has no practical industrial value. It is not suitable for jewelry unless polished, and likely has minimal commercial value.

Geological facts

Goethite and limonite commonly produce yellow-brown streaks and rusty coatings. A streak test on unglazed porcelain and a specific-gravity comparison would help distinguish it from slag, basalt, or a meteorite.

Field identification & locations

Common in weathered iron-bearing ground worldwide, including lateritic soils and sedimentary basins. Test for a brown-yellow streak, weak-to-moderate attraction to a strong magnet, and absence of vesicles or metallic fusion crust; identification remains provisional from the image.