mineral

Iron-oxide-rich limonite/goethite ore

Limonite (principally goethite, α-FeO(OH), with hydrated iron oxides); possible manganese oxides

AI-generated identification · may be incorrect

Earthy to dull, locally botryoidal texture; brown, ochre-yellow, black, and rusty-red colors; generally nonmetallic to submetallic luster. Hardness about 4–5.5 (goethite), variable; no consistent cleavage; typically massive rather than crystalline.

Identified September 10, 2026More mineral →

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Physical properties

Formation & geological history

Forms through oxidation and weathering of iron-bearing sulfide or silicate deposits, commonly in gossans, bogs, lateritic soils, and hydrothermal veins. Exact age cannot be determined from appearance; formation may be geologically recent or ancient.

Uses & applications

Used as iron ore, yellow-brown ochre pigment, and a collector specimen; attractive botryoidal pieces may be displayed, though it is generally not a gemstone.

Geological facts

Limonite is a field term rather than one precisely defined mineral, commonly representing mixtures of hydrated iron oxides. Yellow crusts may include goethite or jarosite, while black patches could be manganese oxides or darker iron oxides.

Field identification & locations

Likely identification is supported by rusty earthy colors, heavy appearance, and yellow-brown botryoidal coatings. A yellow-brown streak, moderate heft, and lack of fizz with dilute acid support iron oxides; common in oxidized ore zones worldwide.