mineral
Limonite Concretion
Hydrated Iron Oxide-Hydroxide, FeO(OH)·nH2O
AI-generated identification · may be incorrectHardness of 4 to 5.5 on the Mohs scale, yellowish-brown to dark brown color, submetallic to earthy luster, amorphous or cryptocrystalline structure.
Identified More mineral →
Explore Limonite Concretion in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 4 to 5.5 on the Mohs scale, yellowish-brown to dark brown color, submetallic to earthy luster, amorphous or cryptocrystalline structure.
Formation & geological history
Formed through the low-temperature oxidation and weathering of iron-bearing minerals in sedimentary environments.
Uses & applications
Historically used as a natural pigment (ochre) and minor iron ore; valued by mineral collectors.
Geological facts
Also known as bog iron, limonite often pseudomorphs after other minerals like pyrite, retaining the original crystal shape while changing composition.
Field identification & locations
Identified by its characteristic yellowish-brown streak and earthy appearance; commonly found in iron-rich weathering zones worldwide.
