Magnetite

Lodestone or loadstone refers to either: Magnetite Source: US Government File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Magnetite Source: US Government File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

• Magnetite, a magnetic mineral form of iron(II), iron(III) oxide Fe₃O₄, one of several iron oxides.

• A piece of intensely magnetic magnetite that was used as an early form of magnetic compass.

Iron, steel and ordinary magnetite are attracted to a magnetic field, including the Earth's magnetic field. Only magnetite with a particular crystalline structure, lodestone, can act as a natural magnet and attract and magnetize iron. The direction pointing nature of lodestone was known as far back as 4th century China, where it was used in geomancy. By the 12th century the Chinese were known to use the lodestone compass for navigation, but far earlier magnetic bacteria (Italian) had learned the trick. Magnetotactic bacteria build miniature magnets inside themselves and use them to determine their orientation relative to the Earth's magnetic field [1]. Magnetite is a ferromagnetic mineral form of iron(II,III) oxide, with chemical formula , one of several iron oxides and a member of the spinel group. ... In physics, magnetism is a phenomenon by which materials exert an attractive or repulsive force on other materials. ... This article is about minerals in the geologic sense; for nutrient minerals see dietary mineral; for the band see Mineral (band). ... Iron(II) oxide, also called ferrous oxide, is a black-colored powder with the chemical formula FeO. It consists of the element iron in the oxidation state of 2 bonded to oxygen. ... Iron(III) oxide - also known as ferric oxide, red iron oxide, synthetic maghemite, rouge,or rust - is one of several oxide compounds of iron, and is most notable for its ferromagnetic properties. ... Iron oxide pigment There are a number of iron oxides: Iron oxides Iron(II) oxide or ferrous oxide (FeO) The black-coloured powder in particular can cause explosions as it readily ignites. ... This article is about the navigational instrument. ... Current flowing through a wire produces a magnetic field (M) around the wire. ... The magnetosphere shields the surface of the Earth from the charged particles of the solar wind. ... In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... Geomancy (from the Latin geo, Earth, mancy prophecy) is a method of divination to interpret markings on the ground or how handfuls of dirt land when you toss them. ...