Magnetite is an iron oxide mineral with the ideal formula Fe3O4 and is an important source of iron. It occurs in a wide range of igneous, metamorphic, sedimentary, and hydrothermal settings and is a major iron mineral in many banded iron formations. Magnetite can also host economically important substituted elements, notably vanadium in vanadiferous magnetite, even though those elements do not appear in its ideal formula.
These elements are often found is this element in the following Deposit Types:
Deposit Type: Banded Iron Formation (BIF) / Superior-type Iron Formation - Large Precambrian iron formations composed of alternating iron-rich and silica-rich layers.
Magnetite is one of the principal iron minerals in oxide-facies Superior-type banded iron formations.
Deposit Type: Magmatic Fe-Ti-V Oxide - Magmatic oxide deposits formed by concentrations of iron-, titanium-, and locally vanadium-bearing minerals.
Magnetite is an important iron-bearing oxide in magmatic Fe-Ti-V systems and may be recovered as an iron product or coproduct.
Deposit Type: Vanadiferous Titanomagnetite (VTM) - Magmatic magnetite-rich deposits in which vanadium is commonly hosted within the magnetite crystal lattice.
Vanadium commonly substitutes for iron within magnetite; the ideal magnetite formula remains Fe3O4 even when the magnetite is vanadium-bearing.