mineral

Iron-rich mineral fragment, possibly limonite/goethite

Limonite (hydrated iron oxides; commonly goethite, FeO(OH), with hematite)

AI-generated identification · may be incorrect

Brown to yellow-brown, earthy to dull/submetallic luster, irregular fracture, and typically no visible crystal faces; hardness about 4–5.5 Mohs and specific gravity roughly 3.3–4.3.

Identified August 14, 2026More mineral →

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Physical properties

Brown to yellow-brown, earthy to dull/submetallic luster, irregular fracture, and typically no visible crystal faces; hardness about 4–5.5 Mohs and specific gravity roughly 3.3–4.3.

Formation & geological history

Forms through weathering and oxidation of iron-bearing minerals, commonly as a soil, crust, or cavity coating; its age depends on the host deposit and may range from recent to ancient.

Uses & applications

Used historically as an iron ore and natural ochre pigment; attractive pieces are mainly collected as mineral specimens, though this small fragment has little commercial value.

Geological facts

“Limonite” is a field and trade term rather than a single pure mineral, because it consists of poorly crystalline hydrated iron oxides.

Field identification & locations

Identify by rusty yellow-brown streak, earthy texture, and association with weathered rocks or iron-rich soils; a magnet test may be weak or negative. Common worldwide, especially in laterites, gossans, and oxidized ore zones.