Limonite and Hematite
Goethite/Hematite mixture (Iron Oxides) · Mineral Specimen / Industrial Mineral
Crystal System
Orthorhombic/Trigonal; typically massive, earthy, or botryoidal habit
Mineral Group
Oxides / Hydroxides
Chemical Formula
FeO(OH)·nH2O and Fe2O3
Formation Process
Sedimentary and secondary weathering process through the oxidation of iron-bearing minerals
About This Crystal
Earthy to metallic specimen featuring reddish-brown and yellowish-brown zones with a sub-metallic luster on fresh surfaces and an opaque, matte texture on weathered faces.
Physical Characteristics
Color: Yellow-brown to reddish-black. Streak: Yellowish-brown (Limonite) to Cherry-Red (Hematite). Specific Gravity: 2.7–4.3. Opaque transparency.
Optical Properties
Isotropic (opaque); sub-metallic to earthy luster with no pleochroism or birefringence visible to the naked eye
Hardness & Durability
Origin Region
Global; common in oxidized zones of iron-rich deposits in regions like the USA, Africa, and Brazil
Hardness & Durability
Mohs hardness: 4.0 - 5.5. Brittle tenacity; lacks distinct cleavage in massive forms.
Care & Maintenance
Clean with a soft brush and water; avoid acids as they may dissolve iron oxides. Store in a dry environment to prevent further hydration.
Rarity & Value
Common; primary value is industrial for iron ore or as a collector mineral for its earthy textures.
Special Characteristics
Pisolitic or botryoidal surface textures; magnetic properties may be present if magnetite inclusions exist.
Lore & History
Historically used as ochre pigments for cave paintings and pottery; traditionally associated with grounding and physical protection in mineral lore.