mineral

Limonite Concretion

FeO(OH)·nH2O

Hardness is 4 to 5.5 on the Mohs scale. Color ranges from yellowish-brown to dark brown with a submetallic to earthy luster.

Identified October 23, 2026More mineral →

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Physical properties

Hardness is 4 to 5.5 on the Mohs scale. Color ranges from yellowish-brown to dark brown with a submetallic to earthy luster.

Formed through the oxidation and weathering of iron-bearing minerals in sedimentary environments.

Used as an iron ore, a pigment for yellow ochre paint, and collected as a geological specimen.

Limonite is not a true distinct mineral species, but rather a mixture of related hydrated iron oxides.

Identified by its characteristic yellowish-brown streak and earthy texture; commonly found worldwide in gossans and weathering zones.

Gneiss or Schist

Gneiss or Mica Schist with Garnet

Limonite

FeO(OH)•nH2O

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Feldspar

Feldspar Group (Tectosilicate, e.g., KAlSi3O8)

Tumbled granite

Granite, a coarse-grained felsic intrusive igneous rock

Pegmatite with Tourmaline and Quartz

Igneous Pegmatite