mineral

Iron-rich weathered rock (probable limonite/goethite)

Limonite, a mixture dominated by goethite (FeO(OH)) and related hydrated iron oxides

AI-generated identification · may be incorrect

Earthy brown to rusty orange, dull to submetallic luster, irregular massive texture, and no obvious cleavage; approximate Mohs hardness 4–5.5, with typically high specific gravity around 3.3–4.3. The image alone cannot confirm mineral identity or distinguish it from ironstone.

Identified September 16, 2026More mineral →

Explore Iron-rich weathered rock (probable limonite/goethite) in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Forms through intense weathering and oxidation of iron-bearing rocks or sulfide deposits, commonly accumulating in soils, cavities, and gossans; generally a modern-to-geologically ancient weathering product rather than a single-age rock.

Uses & applications

Used historically as an iron ore and earth pigment; attractive botryoidal or sharply textured pieces are collected, but this rough specimen has limited commercial value.

Geological facts

Limonite is not a single definitive mineral species but a field term for poorly crystalline hydrated iron oxides. Goethite-rich material may develop yellow-brown streaks and can occur with hematite and quartz.

Field identification & locations

Common in oxidized ore zones worldwide, including Australia, Brazil, the United States, and Europe. A yellow-brown to reddish-brown streak, strong heft, and possible attraction to a magnet help identification; acid and laboratory tests are more diagnostic.