Hematite-Titanomagnetite
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Mineral NameHematite-Titanomagnetite
Chemical FormulaFe2O3 (Hematite); (Fe,Ti)3O4 (Titanomagnetite)
Mohs Hardness5
Streak ColorReddish-brown (Hematite); Black (Titanomagnetite)
CleavageNone (parting in hematite)
FractureUneven to subconchoidal
Specific Gravity5
Colorssteel gray, black, reddish-brown
TransparencyOpaque
Type LocalityGlobal (common in iron-titanium ore deposits)
Mineral GroupOxides
Usesiron ore, titanium ore, pigments, magnetic recording
Associated Mineralsilmenite, pyroxene, olivine, plagioclase
Raritycommon
Description
A microscopic image displaying an intergrowth of two distinct mineral phases: lighter gray, often granular crystals of hematite, and darker gray to black, more blocky crystals of titanomagnetite.
Geological Context
This intergrowth commonly forms in mafic igneous rocks through exsolution processes during cooling, where titanomagnetite solid solutions separate into iron-rich (magnetite/titanomagnetite) and titanium-rich (ilmenite/hematite) phases.
