mineral

Iron-rich rock, possibly limonite/goethite-bearing quartz or weathered ironstone

Limonite (FeO(OH)·nH₂O), commonly mixed with goethite (α-FeO(OH)) and quartz

AI-generated identification · may be incorrect

Mustard-brown to rusty brown, earthy to dull luster, granular texture, and no obvious cleavage; hardness typically 4–5.5 Mohs, specific gravity about 3.3–4.3. The image alone cannot confirm mineral identity or composition.

Identified September 6, 2026More mineral →

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At a glance

Common name: Iron-rich rock, possibly limonite/goethite-bearing quartz or weathered ironstone
Scientific name: Limonite (FeO(OH)·nH₂O), commonly mixed with goethite (α-FeO(OH)) and quartz
Category: mineral
Identified: September 6, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 for a common hand specimen; unusual botryoidal or locality-specific material may sell for $20–$50.

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 through oxidation and hydration of iron-bearing minerals, commonly as a weathering crust, gossan, or soil concretion; generally geologically young relative to its parent rock and may occur in many ages of terrain.

Uses & applications

Iron ores are used in steel production and pigments; attractive pieces may be collected, but this small rough specimen has little commercial value.

Geological facts

Its yellow-brown streak and rusty appearance are characteristic of hydrated iron oxides. A strongly magnetic response would suggest magnetite or maghemite instead.

Field identification & locations

Check streak on unglazed porcelain: limonite gives yellow-brown, while hematite gives red-brown. Test magnetism, hardness, and acid reaction; common in weathered ore deposits worldwide.