Hematite
Hematite (Red Ochre / Specularite Variety) · Mineral Specimen / Industrial Mineral / Pigment Stone
Crystal System
Trigonal system; typically occurs in massive, earthy, botryoidal, or micaceous habits
Mineral Group
Oxides (Hematite group)
Chemical Formula
Fe2O3 (Iron(III) oxide); often includes trace TiO2, Al2O3, or MnO2
Formation Process
Primarily formed via sedimentary precipitation in banded iron formations, hydrothermal veins, or contact metamorphism
About This Crystal
An opaque, deep earthy red to metallic dark grey mineral. This specimen shows a dull, earthy luster with patches of sub-metallic glistening. It exhibits a characteristic rust-red color with granular and massive surface textures.
Physical Characteristics
Color: Reddish-brown to steel gray; Streak: Distinctly cherry red to brownish-red; Specific Gravity: 5.26; Magnetism: Weakly magnetic after heating; Fluorescence: None
Optical Properties
Opaque; metallic specimens are weakly pleochroic; Refractive Index: 2.87 to 3.22 (extremely high but usually not measurable in crystalline mass)
Hardness & Durability
Origin Region
Global; notably Iron Knob (Australia), Minas Gerais (Brazil), Lake Superior (USA), and Cumberland (UK)
Hardness & Durability
Mohs hardness: 5.5 to 6.5; Toughness: Brittle; Sensitivity: Vulnerable to acids; stable under normal light and heat
Care & Maintenance
Avoid acidic cleaners or harsh chemicals; clean with dry cloth or warm soapy water if non-porous; store separately as it may scratch softer stones like fluorite
Rarity & Value
Common; Value is determined by specimen aesthetics or industrial iron content; Specularite var. holds more value for collectors; Earthy red varieties are historically valued as pigments
Special Characteristics
Specularite varieties show micaceous glimmer; Earthy varieties act as natural pigments; high density makes it very heavy for its size
Lore & History
Used by prehistoric humans as 'red ochre' for cave paintings; historically associated with groundness and protection; used by ancient Romans as war paint due to its blood-red streak