mineral
Limonite
FeO(OH)·nH2O
Hardness: 4 to 5.5 on the Mohs scale. Color: Brown, yellowish-brown, or yellow-ochre. Luster: Earthy, submetallic, or silky. Crystal structure: Amorphous (typically occurs as concretionary, mammillary, or earthy masses). Streak: Yellowish-brown.
- Hardness
- 4 to 5
- Color
- Brown, yellowish-brown, or yellow-ochre
- 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 yellow-ochre. Luster: Earthy, submetallic, or silky. Crystal structure: Amorphous (typically occurs as concretionary, mammillary, or earthy masses). Streak: Yellowish-brown.
Formation & geological history
Formed as a secondary mineral resulting from the oxidation and weathering of various iron-bearing minerals, often in sedimentary environments, bogs, and gossans overlying sulfide deposits.
Uses & applications
Historically used as an iron ore and pigment (ochre). Today primarily found in mineral collections and educational kits.
Geological facts
Limonite is not a single distinct mineral, but rather a mixture of related hydrated iron oxide-hydroxide minerals, most notably goethite, lepidocrocite, and jarosite.
Field identification & locations
Can be identified in the field by its characteristic yellowish-brown streak and earthy appearance. Found worldwide, especially in weathered iron ore deposits.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Soil with Mineral Detritus and Quartz Fragments
Regolith / Silicate Mineral Aggregate
sedimentary
Limonite / Goethite (Iron Ore Mineral nodule)
FeO(OH)·nH2O / FeO(OH)
mineral
Schist
Schist
Metamorphic
Septarian Pebble
Septarian nodule / Concretion
sedimentary
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral