mineral

Likely weathered iron-rich rock or slag fragment

Indeterminate; possibly limonite/goethite-bearing rock (FeO(OH)·nH₂O) or industrial iron slag

AI-generated identification · may be incorrect

Dark brown-gray, dull to slightly metallic surface with rusty iron staining; hardness likely about 4–6 if natural ironstone, variable if slag. The rough, elongated form and apparent vesicular/irregular texture prevent reliable identification from the image alone.

Identified September 2, 2026More mineral →

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At a glance

Common name: Likely weathered iron-rich rock or slag fragment
Scientific name: Indeterminate; possibly limonite/goethite-bearing rock (FeO(OH)·nH₂O) or industrial iron slag
Category: mineral
Identified: September 2, 2026
Method: Standard

AI Estimated Value

$1–$10 as an unidentified common specimen; up to $20–$50 if confirmed as an attractive historic slag or unusual ironstone.

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

Natural ironstone forms by oxidation and concentration of iron minerals near Earth’s surface; goethite and limonite commonly form during weathering over millions of years. If slag, it is a human-produced smelting byproduct and not a natural geological rock.

Uses & applications

Iron-rich rock may be collected as a specimen or used historically as iron ore; slag has limited industrial use as aggregate or cement additive. It has little jewelry value.

Geological facts

Magnetism, streak, density, and a fresh broken surface are needed for distinction. A strong magnet and reddish-brown streak support iron minerals, while glassy bubbles, sharp flow textures, and metallic inclusions suggest slag.

Field identification & locations

Common natural sources include banded iron formations and weathering zones; slag is found near historic furnaces, mines, and smelters. Test cautiously with a magnet, streak plate, and specific gravity; avoid assuming it is a meteorite.