mineral
Limonite
FeO(OH)•nH2O
AI-generated identification · may be incorrectHardness: 4 to 5.5 on Mohs scale; Color: Yellow-brown, dark brown, to black; Luster: Dull, earthy, to submetallic; Crystal Structure: Amorphous or microcrystalline; Cleavage: None; Specific Gravity: 2.7 to 4.3
- Hardness
- 4 to 5
- Color
- Yellow-brown, dark brown, to black
- Luster
- Dull, earthy, to submetallic
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 Mohs scale; Color: Yellow-brown, dark brown, to black; Luster: Dull, earthy, to submetallic; Crystal Structure: Amorphous or microcrystalline; Cleavage: None; Specific Gravity: 2.7 to 4.3
Formation & geological history
Formed as a secondary mineral resulting from the oxidation and weathering of various iron-bearing minerals, often in sedimentary environments, gossans, or bog iron deposits.
Uses & applications
Historically used as a pigment (ochre), a minor ore of iron, and occasionally cut and polished into ornamental stones or jewelry.
Geological facts
Limonite is not a single distinct mineral, but rather a mixture of related hydrated iron oxides and hydroxides, most commonly goethite and lepidocrocite.
Field identification & locations
Identified easily by its characteristic yellowish-brown streak. Commonly found worldwide wherever iron-rich rocks undergo weathering.
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