Class : Oxides and hydroxides
    Subclass : Oxides
    Crystal system : Cubic
    Chemistry : MgFe₂O₄
    Rarity : Uncommon

Magnesioferrite is essentially the spinel of volcanoes. It forms a continuous series with magnetite. Although this spinel is also known in many sometimes more original contexts (burning coal mines, maerls subjected to high temperature combustion of coal seams, kimberlites, carbonatites, metamorphic dolomites, etc...), it is essentially a mineral which crystallizes in fumarolic deposits. Its name derives from its chemical composition : magnesium + iron. Magnesioferrite rarely occurs in octahedral crystals of 5 mm at most, more often in irregular grains or aggregates, brownish black in color.

Main photo : Alluvial maghemite from the Carapooee gold mine, Victoria, Australia © Judy Rowe

Twins are common on {111}.

No fakes recorded for this mineral species.