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Roger Weller, geology instructor
Chemical Group: oxide
Chemical Formula: Fe3O4
Color: black Steak: black
Luster: splendent to dull metallic Transparency: opaque
Hardness: 5.5 to 6.5
Specific Gravity: 5.20
Crystal Forms and Habits: Isometric system
Magnetite commonly forms octahedrons.
It is commonly massive or granular.
Mineral Associations: Magnetite is found in igneous rocks (usually basaltic) and
in metamorphic environments
Identifying Characteristics: highly magnetic, hence the source of its name.
Uses: iron ore
Toxicity: when-swallowed- low when inhaled- high
Additional Information: Some forms of magnetite are natural magnets and are