Magnetite

It is a black, opaque, submetallic to metallic mineral with a Mohs hardness between 5 and 6.5. It is often found in the form of isometric crystals. It is the most strongly magnetic mineral found in nature. Magnetite is ferromagnetic, which means that magnetite particles are attracted to an external magnetic field; when magnetized, magnetite particles can act like tiny magnets. Magnetite is ferromagnetic because it contains both Fe⁺² and Fe⁺³ ions, both of which have many unpaired electrons.

Normal magnetite is attracted to a magnet, but some specimens are automagnetized and have the ability to attract small pieces of iron, small pieces of magnetite, and other magnetic objects. This form of magnetite, known as “lodestone. Magnetite is primarily used to extract iron in the form of pig iron or sponge iron. This produced iron is then used to make steel. Magnetite is also used as a catalyst. It is the catalyst used in the industrial-scale production of ammonia.