mineral
Limonite
FeO(OH)·nH2O
AI-generated identification · may be incorrectHardness: 4 to 5.5 on the Mohs scale. Color: Brown, yellowish-brown, or ochre-yellow. Luster: Earthy, submetallic, or silky. Crystal structure: Amorphous or microcrystalline, typically forming as concretionary, mammillary, or earthy masses. Specific gravity: 2.7 to 4.3.
- Hardness
- 4 to 5
- Color
- Brown, yellowish-brown, or ochre-yellow
- Luster
- Earthy, submetallic, or silky
Identified More mineral →
Explore Limonite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 4 to 5.5 on the Mohs scale. Color: Brown, yellowish-brown, or ochre-yellow. Luster: Earthy, submetallic, or silky. Crystal structure: Amorphous or microcrystalline, typically forming as concretionary, mammillary, or earthy masses. Specific gravity: 2.7 to 4.3.
Formation & geological history
Forms as an alteration product of other iron-rich minerals such as magnetite and pyrite, typically in weathering environments, bogs, and sedimentary settings.
Uses & applications
Historically used as a low-grade iron ore and as an earthy yellow pigment (ochre) for paints and ceramics.
Geological facts
Limonite is not a single distinct mineral species, but rather a mixture of related hydrated iron oxides and hydroxides, most commonly goethite and lepidocrocite.
Field identification & locations
Can be identified in the field by its characteristic yellowish-brown streak, earthy texture, and association with weathered iron deposits. Found worldwide.
More like this
Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous
Septarian Pebble
Septarian nodule / Concretion
sedimentary