Editing Iron oxide (section)

==Stoichiometries== 
[[File:IronOxidePigmentUSGOV.jpg|thumb|Iron oxide pigment. The brown color indicates that iron is at the oxidation state +3.|261px]]
[[File:Red and green iron oxides.jpg|thumb|upright|Green and reddish brown stains on a limestone core sample, respectively corresponding to oxides/hydroxides of Fe<sup>2+</sup> and Fe<sup>3+</sup>.]]

Iron oxides feature as [[ferrous]] ([[Iron(II)|Fe(II)]]) or [[Iron(III)|ferric]] ([[Iron(III)|Fe(III)]]) or both. They adopt [[Octahedral molecular geometry|octahedral]] or [[Tetrahedral molecular geometry|tetrahedral coordination geometry]].  Only a few oxides are significant at the earth's surface, particularly wüstite, magnetite, and hematite.

* Oxides of Fe<sup>II</sup>
** FeO:  [[iron(II) oxide]], [[wüstite]] 
* Mixed oxides of Fe<sup>II</sup> and Fe<sup>III</sup>
** Fe<sub>3</sub>O<sub>4</sub>: [[Iron(II,III) oxide]], [[magnetite]] 
** Fe<sub>4</sub>O<sub>5</sub><ref>{{cite journal|title=Discovery of the recoverable high-pressure iron oxide Fe4O5|date=Oct 2011 | doi=10.1073/pnas.1107573108 |pmid=21969537 | volume=108|issue=42|journal=Proceedings of the National Academy of Sciences|pages=17281–17285|bibcode=2011PNAS..10817281L|pmc=3198347|last1=Lavina |first1=B. |last2=Dera |first2=P. |last3=Kim |first3=E. |last4=Meng |first4=Y. |last5=Downs |first5=R. T. |last6=Weck |first6=P. F. |last7=Sutton |first7=S. R. |last8=Zhao |first8=Y. |doi-access=free }}</ref>
** Fe<sub>5</sub>O<sub>6</sub><ref>{{cite journal|title = Synthesis of Fe5O6|journal = Science Advances|volume = 1|issue = 5|pages = e1400260|doi = 10.1126/sciadv.1400260|pmid = 26601196|year = 2015|last1 = Lavina|first1 = Barbara|last2 = Meng|first2 = Yue|pmc = 4640612}}</ref>
** Fe<sub>5</sub>O<sub>7</sub><ref name = "oxides">{{cite journal| title = Structural complexity of simple Fe2O3 at high pressures and temperatures| journal = Nature Communications| volume = 7| pages = 10661| doi = 10.1038/ncomms10661| pmid = 26864300| pmc = 4753252| year = 2016| last1 = Bykova| first1 = E.| last2 = Dubrovinsky| first2 = L.| last3 = Dubrovinskaia| first3 = N.| last4 = Bykov| first4 = M.| last5 = McCammon| first5 = C.| last6 = Ovsyannikov| first6 = S. V.| last7 = Liermann| first7 = H. -P.| last8 = Kupenko| first8 = I.| last9 = Chumakov| first9 = A. I.| last10 = Rüffer| first10 = R.| last11 = Hanfland| first11 = M.| last12 = Prakapenka| first12 = V.| bibcode = 2016NatCo...710661B}}</ref>
** Fe<sub>25</sub>O<sub>32</sub><ref name="oxides" />
**Fe<sub>13</sub>O<sub>19</sub><ref>{{cite journal| title = The crystal structures of Mg2Fe2C4O13, with tetrahedrally coordinated carbon, and Fe13O19, synthesized at deep mantle conditions| journal = American Mineralogist| volume = 100| issue = 8–9| pages = 2001–2004| doi = 10.2138/am-2015-5369| year = 2015| last1 = Merlini| first1 = Marco| last2 = Hanfland| first2 = Michael| last3 = Salamat| first3 = Ashkan| last4 = Petitgirard| first4 = Sylvain| last5 = Müller| first5 = Harald| bibcode = 2015AmMin.100.2001M| s2cid = 54496448}}</ref>
* Oxides of Fe<sup>III</sup>
** Fe<sub>2</sub>O<sub>3</sub>: [[iron(III) oxide]] 
*** α-Fe<sub>2</sub>O<sub>3</sub>: [[iron(III) oxide#Alpha phase|alpha phase]], [[hematite]] 
*** β-Fe<sub>2</sub>O<sub>3</sub>: [[iron(III) oxide#Other solid phases|beta phase]]
*** γ-Fe<sub>2</sub>O<sub>3</sub>: [[iron(III) oxide#Gamma phase|gamma phase]], [[maghemite]] 
*** ε-Fe<sub>2</sub>O<sub>3</sub>: [[iron(III) oxide#Other solid phases|epsilon phase]]