mineral

Possible iron-rich concretion or weathered ironstone

Goethite/limonite-rich ironstone; exact identification requires testing

AI-generated identification · may be incorrect

Small rounded brown-gold specimen with dull to earthy luster and irregular botryoidal texture. Likely hardness about 4–5.5 Mohs, opaque, with no visible cleavage; may leave a yellow-brown streak and feel relatively heavy for its size.

Identified August 11, 2026More mineral →

Explore Possible iron-rich concretion or weathered ironstone 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

Probably formed by weathering and oxidation of iron-bearing minerals, producing hydrated iron oxides such as goethite and limonite. Such materials commonly develop as soil concretions or coatings in near-surface environments; age cannot be determined from the image.

Uses & applications

Mostly a collecting specimen; iron oxides are mined as iron ore and used historically as ochre pigments. This small piece has little industrial or jewelry value.

Geological facts

The golden-brown color is typical of hydrated iron oxides, but the image cannot distinguish them reliably from brown jasper, slag, or another iron-rich material.

Field identification & locations

Check density, streak, magnetism, and hardness: a yellow-brown streak and possible weak magnetism support ironstone, while glassy fracture or a white streak suggests another material. Common in weathered soils, mine dumps, and iron-rich sedimentary settings.