Editing Ilmenite (section)

== Paragenesis ==
Ilmenite is a common accessory mineral found in [[metamorphic rock|metamorphic]] and [[igneous rock]]s.<ref name=HBM/> It is found in large concentrations in [[layered intrusion]]s where it forms as part of a [[cumulate rock|cumulate]] layer within the intrusion. Ilmenite generally occurs in these cumulates together with [[orthopyroxene]]<ref>{{cite journal |last1=Wilson |first1=J.R. |last2=Robins |first2=B. |last3=Nielsen |first3=F.M. |last4=Duchesne |first4=J.C. |last5=Vander Auwera |first5=J. |title=The Bjerkreim-Sokndal Layered Intrusion, Southwest Norway |journal=Developments in Petrology |date=1996 |volume=15 |pages=231–255 |doi=10.1016/S0167-2894(96)80009-1|bibcode=1996DevPe..15..231W |hdl=2268/550 |isbn=9780444817686 |hdl-access=free }}</ref> or in combination with [[plagioclase]] and [[apatite]] (''[[nelsonite]]'').<ref>{{cite journal |last1=Charlier |first1=Bernard |last2=Sakoma |first2=Emmanuel |last3=Sauvé |first3=Martin |last4=Stanaway |first4=Kerry |last5=Auwera |first5=Jacqueline Vander |last6=Duchesne |first6=Jean-Clair |title=The Grader layered intrusion (Havre-Saint-Pierre Anorthosite, Quebec) and genesis of nelsonite and other Fe–Ti–P ores |journal=Lithos |date=March 2008 |volume=101 |issue=3–4 |pages=359–378 |doi=10.1016/j.lithos.2007.08.004|bibcode=2008Litho.101..359C |hdl=2268/1893 |hdl-access=free }}</ref>

[[Magnesium|Magnesian]] ilmenite is formed in kimberlites as part of the MARID association of minerals ([[mica]]-[[amphibole]]-[[rutile]]-ilmenite-[[diopside]]) assemblage of [[Biotite|glimmerite]] [[xenolith]]s.<ref>{{cite journal |last1=Dawson |first1=J.Barry |last2=Smith |first2=Joseph V. |title=The MARID (mica-amphibole-rutile-ilmenite-diopside) suite of xenoliths in kimberlite |journal=Geochimica et Cosmochimica Acta |date=February 1977 |volume=41 |issue=2 |pages=309–323 |doi=10.1016/0016-7037(77)90239-3|bibcode=1977GeCoA..41..309D |doi-access=free }}</ref> [[Manganese|Manganiferous]] ilmenite is found in [[granite|granitic]] rocks<ref name=SasakiEtal2003/> and also in [[carbonatite]] intrusions where it may also contain anomalously high amounts of [[niobium]].<ref>{{cite journal |last1=Cordeiro |first1=Pedro F.O. |last2=Brod |first2=José A. |last3=Dantas |first3=Elton L. |last4=Barbosa |first4=Elisa S.R. |title=Mineral chemistry, isotope geochemistry and petrogenesis of niobium-rich rocks from the Catalão I carbonatite-phoscorite complex, Central Brazil |journal=Lithos |date=August 2010 |volume=118 |issue=3–4 |pages=223–237 |doi=10.1016/j.lithos.2010.04.007|bibcode=2010Litho.118..223C }}</ref>

Many [[mafic]] igneous rocks contain grains of intergrown magnetite and ilmenite, formed by the [[oxidation]] of [[ulvospinel]].<ref name="BuddingtonLindsley1964"/>