Editing Iron(II,III) oxide (section)

==Properties==
[[File:Magnetite.jpg|thumb|240px|Sample of [[magnetite]], naturally occurring Fe<sub>3</sub>O<sub>4</sub>.]]

Fe<sub>3</sub>O<sub>4</sub> is [[ferrimagnetic]] with a [[Curie point|Curie temperature]] of {{Convert|858|K|C}}. There is a phase transition at {{Convert|120|K|C}}, called [[Verwey transition]] where there is a discontinuity in the structure, conductivity and magnetic properties.<ref>{{cite journal |title = Electronic Conduction of Magnetite (Fe<sub>3</sub>O<sub>4</sub>) and its Transition Point at Low Temperatures | vauthors = Verwey EJ |journal = [[Nature (journal)|Nature]] |volume = 144 |pages = 327–328 (1939) |doi = 10.1038/144327b0 |year = 1939 | issue=3642|bibcode = 1939Natur.144..327V |s2cid = 41925681 }}</ref> This effect has been extensively investigated and whilst various explanations have been proposed, it does not appear to be fully understood.<ref>{{cite journal| vauthors = Walz F |title=The Verwey transition - a topical review |journal=Journal of Physics: Condensed Matter |date=2002 |volume=14 |issue=12 |pages=R285–R340 |doi=10.1088/0953-8984/14/12/203|s2cid=250773238 }}</ref>

While it has much higher [[electrical resistivity]] than iron metal (96.1 nΩ m), Fe<sub>3</sub>O<sub>4</sub>'s electrical resistivity (0.3 mΩ m <ref>{{cite journal| vauthors = Itai R |title=Electrical resistivity of Magnetite anodes |journal=Journal of the Electrochemical Society |date=1971 |volume=118 |issue=10 |page=1709 |doi=10.1149/1.2407817 |bibcode=1971JElS..118.1709I |url=http://www.chlorates.exrockets.com/magnetite/jes1971.html|url-access=subscription }}</ref>) is significantly lower than that of [[iron(III) oxide|Fe<sub>2</sub>O<sub>3</sub>]] (approx kΩ m). This is ascribed to electron exchange between the Fe<sup>II</sup> and Fe<sup>III</sup> centres in Fe<sub>3</sub>O<sub>4</sub>.<ref name = "Greenwood"/>