mineral

Iron-rich rock, possibly limonite or goethite

Likely goethite (α-FeO(OH)) and/or limonite (iron oxides/oxyhydroxides); identification is uncertain from the image alone

AI-generated identification · may be incorrect

Small, irregular brown specimen with a dull to slightly metallic, reflective surface. Goethite has Mohs hardness 5–5.5, orthorhombic crystals, and no prominent cleavage; specific gravity is about 3.3–4.3.

Identified October 16, 2026More mineral →

Explore Iron-rich rock, possibly limonite or goethite in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Iron-rich rock, possibly limonite or goethite
Scientific name: Likely goethite (α-FeO(OH)) and/or limonite (iron oxides/oxyhydroxides); identification is uncertain from the image alone
Category: mineral
Identified: October 16, 2026
Method: Standard

AI Estimated Value

About $1–$10 USD for a small, common rough specimen; more if testing reveals an uncommon, well-crystallized mineral.

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

Iron oxyhydroxides commonly form through chemical weathering and oxidation of iron-bearing minerals, or precipitate from iron-rich waters; they occur in many geological ages and settings.

Uses & applications

Iron ores are used as sources of iron, while attractive botryoidal or crystalline specimens are collected; this small rough piece has no evident construction use.

Geological facts

Limonite is a field term for mixtures of hydrated iron oxides rather than a single mineral species.

Field identification & locations

The earthy brown color and bright, uneven reflective patches suggest an iron-rich specimen, but a fresh streak and hardness tests would help distinguish goethite from other iron minerals. Common in weathered iron deposits worldwide.