mineral

Weathered iron-rich rock, possibly limonite/goethite-bearing breccia

Hydrated iron oxides/hydroxides, mainly limonite (mixture) and goethite, FeO(OH)·nH₂O

AI-generated identification · may be incorrect

Small irregular brown-black specimen with rusty reddish-brown patches and a dull to slightly metallic luster. Likely hardness about 4–5.5 Mohs, no obvious cleavage, and relatively high density; the image is insufficient to confirm crystal structure or exact composition.

Identified August 17, 2026More mineral →

Explore Weathered iron-rich rock, possibly limonite/goethite-bearing breccia 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: Weathered iron-rich rock, possibly limonite/goethite-bearing breccia
Scientific name: Hydrated iron oxides/hydroxides, mainly limonite (mixture) and goethite, FeO(OH)·nH₂O
Category: mineral
Identified: August 17, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 as a common fragment; up to about $20–$50 if it proves unusually crystalline, dense, or locality-documented.

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

Probably formed by oxidation and weathering of an iron-bearing sulfide or igneous/metamorphic rock, producing a limonite/goethite-rich crust or fragment. Such material is geologically young relative to its parent rock and commonly forms in soils, fractures, and mine dumps.

Uses & applications

Iron oxides are important iron ores and pigments; attractive botryoidal or crystalline goethite specimens are collected. This small, heavily weathered piece has little industrial or jewelry value.

Geological facts

The dark areas may include manganese oxides, magnetite, or residual sulfides, so “limonite” is a field term rather than a single mineral. A strong magnet, streak, and density test would substantially improve identification.

Field identification & locations

A yellow-brown to reddish-brown streak, earthy appearance, and possible weak magnetism support iron oxides. The reported Kuzbass-region location is plausible for weathered iron-bearing material; test streak on unglazed porcelain, magnetism, and avoid acid unless necessary.