mineral
Limonite Geode / Ironstone Nodule
Hydrated Iron Oxide Hydroxide (FeO(OH)·nH2O)
AI-generated identification · may be incorrectHardness varies from 4 to 5.5 on the Mohs scale, color ranges from yellowish-brown, dark brown to black, luster is submetallic to earthy, amorphous or microcrystalline structure, specific gravity is 2.7 to 4.3.
Identified More mineral →
Explore Limonite Geode / Ironstone Nodule in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness varies from 4 to 5.5 on the Mohs scale, color ranges from yellowish-brown, dark brown to black, luster is submetallic to earthy, amorphous or microcrystalline structure, specific gravity is 2.7 to 4.3.
Formation & geological history
Formed by the weathering and oxidation of iron-bearing sulfide minerals, silicates, and carbonates in sedimentary environments or hydrothermal veins.
Uses & applications
Used historically as an iron ore, a pigment (ochre), and as a mineral specimen for collectors.
Geological facts
Limonite is not a true distinct mineral species, but rather a catch-all term for natural mixtures of iron oxide minerals, mostly goethite, lepidocrocite, and hematite.
Field identification & locations
Identified by its characteristic yellowish-brown streak, earthy texture, and hollow nodular form containing secondary mineral linings. 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