Ilmenite

{{Short description|Titanium-iron(II) oxide mineral}} {{Use dmy dates|date=April 2022}} {{Infobox mineral | name = Ilmenite | category = Oxide mineral | boxwidth = | boxbgcolor = | image = Ilmenite-155036.jpg | imagesize = | caption = Ilmenite from Miass, Ilmen Mts, Chelyabinsk Oblast', Southern Urals, Urals Region, Russia. 4.5 x 4.3 x 1.5 cm | formula = Iron(II) titanium oxide, {{Chem2|Fe^{II}TiO3}} | IMAsymbol = Ilm<ref>{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|doi-access=free}}</ref> | strunz = 4.CB.05 | dana = 04.03.05.01 | system = Trigonal | class = Rhombohedral ({{overline|3}}) <br/>H-M symbol: ({{overline|3}}) | symmetry = ''R''{{overline|3}} (no. 148) | unit cell = a = 5.08854(7) <br/>c = 14.0924(3)&nbsp;[Å]: Z&nbsp;=&nbsp;6 | color = Iron-black; gray with a brownish tint in reflected light | habit = Granular to massive and lamellar exsolutions in hematite or magnetite | twinning = {0001} simple, {10{{overline|1}}1} lamellar | cleavage = Absent; parting on {0001} and {10{{overline|1}}1} | fracture = Conchoidal to subconchoidal | tenacity = Brittle | mohs = 5–6 | luster = Metallic to submetallic | refractive = | opticalprop = Uniaxial (–) | birefringence = Strong; O: pinkish brown, E: dark brown (bireflectance) | pleochroism = | streak = Black | gravity = 4.70–4.79 | density = | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Opaque | other = Weakly magnetic; Liquidus = 1710°C (peritectic) <ref>Eriksen et al. (2007). "Equilibrium between Liquid Fe-Ti-O Slags and Metallic Iron." Steel Research International. Vol 78. No. 9. {{doi|10.1002/srin.200706268}}</ref> | references = <ref>{{cite web |last1=Barthelmy |first1=David |title=Ilmenite Mineral Data |url=https://webmineral.com/data/Ilmenite.shtml |website=Mineralogy Database |publisher=Webmineral.com |access-date=12 February 2022 |date=2014}}</ref><ref name="HBM">{{cite book |editor-first1=John W. |editor-last1=Anthony |editor-first2=Richard A. |editor-last2=Bideaux |editor-first3=Kenneth W. |editor-last3=Bladh |editor-first4=Monte C. |editor-last4=Nichols |title=Handbook of Mineralogy |publisher=Mineralogical Society of America |location=Chantilly, VA, USA |url=http://rruff.geo.arizona.edu/doclib/hom/ilmenite.pdf |access-date=12 February 2022 |chapter=Ilmenite}}</ref><ref name="Mindat">{{mindat|id=2013|name=Ilmenite}}</ref> }}

'''Ilmenite''' is a titanium-iron(II) oxide mineral with the idealized formula {{Chem2|FeTiO3}}. It is a weakly magnetic black or steel-gray solid. Ilmenite is the most important ore of titanium<ref>Heinz Sibum, Volker Günther, Oskar Roidl, Fathi Habashi, Hans Uwe Wolf, "Titanium, Titanium Alloys, and Titanium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a27_095}}</ref> and the main source of titanium dioxide, which is used as white pigment in paints, printing inks,<ref>{{Cite web|url=http://www.sanbohk.com/uploadfiles/2014-2/2014211105416156.pdf|title=Sachtleben RDI-S|access-date=2018-12-25|archive-date=2018-12-25|archive-url=https://web.archive.org/web/20181225130335/http://www.sanbohk.com/uploadfiles/2014-2/2014211105416156.pdf|url-status=dead}}</ref> fabrics, plastics, paper, sunscreen, food and cosmetics.<ref>{{Cite web|url=http://www.mineralcommodities.com/products/|title=Products|website=Mineral Commodities Ltd|access-date=2016-08-08}}</ref>

== Structure and properties == Ilmenite is a heavy (specific gravity 4.7), moderately hard (Mohs hardness 5.6 to 6), opaque black mineral with a submetallic luster.<ref name="KleinHurlbut1993" /> It is almost always massive, with thick tabular crystals being quite rare. It shows no discernible cleavage, breaking instead with a conchoidal to uneven fracture.<ref name="Sinkankas1964" />

Ilmenite crystallizes in the trigonal system with space group ''R''{{overline|3}}.<ref name="Nesse2000">{{cite book |last1=Nesse |first1=William D. |title=Introduction to mineralogy |date=2000 |publisher=Oxford University Press |location=New York |isbn=9780195106916 |pages=366–367}}</ref><ref name="HBM" /> The ilmenite crystal structure consists of an ordered derivative of the corundum structure; in corundum all cations are identical but in ilmenite Fe²⁺ and Ti⁴⁺ ions occupy alternating layers perpendicular to the trigonal c axis.

Pure ilmenite is paramagnetic (showing only very weak attraction to a magnet), but ilmenite forms solid solutions with hematite that are weakly ferromagnetic and so are noticeably attracted to a magnet. Natural deposits of ilmenite usually contain intergrown or exsolved magnetite that also contribute to its ferromagnetism.<ref name="KleinHurlbut1993">{{cite book |last1=Klein |first1=Cornelis |last2=Hurlbut |first2=Cornelius S. Jr. |title=Manual of mineralogy : (after James D. Dana) |date=1993 |publisher=Wiley |location=New York |isbn=047157452X |edition=21st |pages=380–381}}</ref>

Ilmenite is distinguished from hematite by its less intensely black color and duller appearance and its black streak, and from magnetite by its weaker magnetism.<ref name="Sinkankas1964">{{cite book |last1=Sinkankas |first1=John |title=Mineralogy for amateurs. |date=1964 |publisher=Van Nostrand |location=Princeton, N.J. |isbn=0442276249 |pages=328–329}}</ref><ref name="KleinHurlbut1993" />

<gallery> Image:Ilmenite.GIF|Crystal structure of ilmenite File:Ilmenite-65675.jpg|Ilmenite from Froland, Aust-Agder, Norway; 4.1 × 4.1 × 3.8&nbsp;cm File:Ilmenite and hematite under normal light.jpg|Ilmenite and hematite under normal light File:Ilmenite and hematite under polarized light.jpg|Ilmenite and hematite under polarized light </gallery>

== Discovery == In 1791, William Gregor discovered a deposit of black sand in a stream that runs through the valley just south of the village of Manaccan (Cornwall), and identified for the first time titanium as one of the constituents of the main mineral in the sand.<ref>Gregor, William (1791) "Beobachtungen und Versuche über den Menakanit, einen in Cornwall gefundenen magnetischen Sand" (Observations and experiments regarding menaccanite [i.e., ilmenite], a magnetic sand found in Cornwall), ''Chemische Annalen'' …, '''1''', [https://books.google.com/books?id=ZFAyAQAAMAAJ&pg=PA40 pp. 40–54], [https://books.google.com/books?id=ZFAyAQAAMAAJ&pg=PA103 103–119.]</ref><ref>{{cite book|title=Nature's Building Blocks: An A-Z Guide to the Elements|last1=Emsley|first1=John|publisher=Oxford University Press|year=2001|location=Oxford, England, UK|isbn=978-0-19-850340-8 |chapter=Titanium |chapter-url=https://books.google.com/books?id=j-Xu07p3cKwC|url-access=registration|url=https://archive.org/details/naturesbuildingb0000emsl}}</ref><ref>{{cite book |last1=Woodford |first1=Chris|author1-link=Chris Woodford (author) |title=Titanium |date=2003 |publisher=Benchmark Books |location=New York |isbn=9780761414612 |page=7 |url=https://books.google.com/books?id=84W_FvfskTsC&dq=history+of+titanium&pg=PA4 |access-date=22 February 2022}}</ref> Gregor named this mineral '''''manaccanite'''''.<ref>{{cite journal |last1=Habashi |first1=Fathi |title=Historical Introduction to Refractory Metals |journal=Mineral Processing and Extractive Metallurgy Review |date=January 2001 |volume=22 |issue=1 |pages=25–53 |doi=10.1080/08827509808962488|bibcode=2001MPEMR..22...25H |s2cid=100370649 }}</ref> The same mineral was found in the Ilmensky Mountains, near Miass, Russia, and named ''ilmenite''.<ref name="Sinkankas1964" />

== Mineral chemistry == Pure ilmenite has the composition {{chem2|FeTiO3}}. However, ilmenite most often contains appreciable quantities of magnesium and manganese and up to 6 wt% of hematite, {{chem2|Fe2O3}}, substituting for {{chem2|FeTiO3}} in the crystal structure. Thus the complete chemical formula can be expressed as {{chem2|(Fe,Mg,Mn,Ti)O3}}.<ref name="KleinHurlbut1993" /> Ilmenite forms a solid solution with geikielite ({{Chem|Mg||Ti||O|3}}) and pyrophanite ({{Chem|Mn||Ti||O|3}}) which are magnesian and manganiferous end-members of the solid solution series.<ref name="HBM" />

Although ilmenite is typically close to the ideal {{Chem|Fe||Ti||O|3}} composition, with minor mole percentages of Mn and Mg,<ref name="HBM" /> the ilmenites of kimberlites usually contain substantial amounts of geikielite molecules,<ref>{{cite journal |last1=Wyatt |first1=Bruce A. |last2=Baumgartner |first2=Mike |last3=Anckar |first3=Eva |last4=Grutter |first4=Herman |title=Compositional classification of "kimberlitic" and "non-kimberlitic" ilmenite |journal=Lithos |date=September 2004 |volume=77 |issue=1–4 |pages=819–840 |doi=10.1016/j.lithos.2004.04.025|bibcode=2004Litho..77..819W |s2cid=140539776 }}</ref> and in some highly differentiated felsic rocks ilmenites may contain significant amounts of pyrophanite molecules.<ref name="SasakiEtal2003">{{cite journal |last1=Sasaki |first1=Kazuhiro |last2=Nakashima |first2=Kazuo |last3=Kanisawa |first3=Satoshi |title= Pyrophanite and high Mn ilmenite discovered in the Cretaceous Tono pluton, NE Japan|journal=Neues Jahrbuch für Mineralogie - Monatshefte |date=15 July 2003 |volume=2003 |issue=7 |pages=302–320 |doi=10.1127/0028-3649/2003/2003-0302}}</ref>

At temperatures above {{convert|950|C||sp=us}}, there is a complete solid solution between ilmenite and hematite. There is a miscibility gap at lower temperatures, resulting in a coexistence of these two minerals in rocks but no solid solution.<ref name="KleinHurlbut1993" /> This coexistence may result in exsolution lamellae in cooled ilmenites with more iron in the system than can be homogeneously accommodated in the crystal lattice.<ref>{{cite book |last1=Weibel |first1=Rikke |last2=Friis |first2=Henrik |title=Heavy Minerals in Use |chapter=Chapter 10 Alteration of Opaque Heavy Minerals as a Reflection of the Geochemical Conditions in Depositional and Diagenetic Environments |series=Developments in Sedimentology |date=2007 |volume=58 |pages=277–303 |doi=10.1016/S0070-4571(07)58010-6|bibcode=2007DevS...58..277W |isbn=9780444517531 }}</ref> Ilmenite containing 6 to 13 percent {{chem2|Fe2O3}} is sometimes described as ''ferrian ilmenite''.<ref name="BuddingtonLindsley1964">{{cite journal |last1=Buddington |first1=A. F. |last2=Lindsley |first2=D. H. |title=Iron-Titanium Oxide Minerals and Synthetic Equivalents |journal=Journal of Petrology |date=1 January 1964 |volume=5 |issue=2 |pages=310–357 |doi=10.1093/petrology/5.2.310}}</ref><ref name="MurphyFrick2006">{{cite book |last1=Murphy |first1=P. |last2=Frick |first2=L. |year=2006 |chapter=Titanium |title=Industrial minerals & rocks: commodities, markets, and uses |editor-last1=Kogel |editor-first1=J. |publisher=SME |pages=987–1003 |isbn=9780873352338 |url=https://books.google.com/books?id=zNicdkuulE4C&q=Titanium |access-date=21 February 2022}}</ref>

Ilmenite alters or weathers to form the pseudo-mineral leucoxene, a fine-grained yellowish to grayish or brownish material<ref name="KleinHurlbut1993" /><ref>{{cite journal |last1=Mücke |first1=A. |last2=Bhadra Chaudhuri |first2=J.N. |title=The continuous alteration of ilmenite through pseudorutile to leucoxene |journal=Ore Geology Reviews |date=February 1991 |volume=6 |issue=1 |pages=25–44 |doi=10.1016/0169-1368(91)90030-B|bibcode=1991OGRv....6...25M }}</ref> enriched to 70% or more of {{chem2|TiO2}}.<ref name="MurphyFrick2006" /> Leucoxene is an important source of titanium in heavy mineral sands ore deposits.<ref name="VanGosenEtal2014">{{cite journal |last1=Van Gosen |first1=Bradley S. |last2=Fey |first2=David L. |last3=Shah |first3=Anjana K. |last4=Verplanck |first4=Philip L. |last5=Hoefen |first5=Todd M. |title=Deposit model for heavy-mineral sands in coastal environments |journal=U.S. Geological Survey Scientific Investigations Report |series=Scientific Investigations Report |date=2014 |volume=201--5070-L |page=13 |doi=10.3133/sir20105070L|doi-access=free |bibcode=2014usgs.rept...13V }}</ref>

== Paragenesis == Ilmenite is a common accessory mineral found in igneous and high-grade metamorphic rocks.<ref name="HBM" /> It is found in large concentrations in layered intrusions where it forms as part of a cumulate layer within the intrusion. Ilmenite generally occurs in these cumulates together with orthopyroxene<ref>{{cite book |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=Layered Intrusions |chapter=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>

Magnesian ilmenite is formed in kimberlites as part of the MARID association of minerals (mica-amphibole-rutile-ilmenite-diopside) assemblage of glimmerite xenoliths.<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> Manganiferous ilmenite is found in 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" />

== Processing and consumption == [[File:Tellnes.jpg|thumb|300px|Tellnes opencast ilmenite mine, Sokndal Municipality, Norway]]

Most ilmenite is mined for titanium dioxide production.<ref>{{Cite web|url=http://www.mineralcommodities.com/products/industry-fundamentals/|title=Industry Fundamentals|website=Mineral Commodities Ltd|access-date=2016-08-08|archive-date=2016-10-07|archive-url=https://web.archive.org/web/20161007145819/http://www.mineralcommodities.com/products/industry-fundamentals/|url-status=dead}}</ref> Ilmenite and titanium dioxide are used in the production of titanium metal.<ref>{{Cite journal|last=Kroll|first=W|title=The production of ductile titanium|journal= Transactions of the Electrochemical Society|volume=78|pages=35–47|doi=10.1149/1.3071290|year=1940}}</ref><ref>{{Cite journal|last=Seki|first=Ichiro|title=Reduction of titanium dioxide to metallic titanium by nitridization and thermal decomposition|url=https://www.jstage.jst.go.jp/article/matertrans/58/3/58_MK201601/_pdf|journal=Materials Transactions|volume=58|issue= 3|pages=361–366|doi=10.2320/matertrans.MK201601|year=2017|doi-access=free}}</ref>

Titanium dioxide is most used as a white pigment, and the major consuming industries for TiO₂ pigments are paints and surface coatings, plastics, and paper and paperboard. Per capita consumption of TiO₂ in China is about 1.1 kilograms per year, compared with 2.7 kilograms for Western Europe and the United States.<ref>{{Cite web|url=https://ihsmarkit.com/products/titanium-dioxide-chemical-economics-handbook.html|title=Titanium Dioxide Chemical Economics Handbook |work=IHS Markit }}</ref>

thumb|Estimated world production of titanium concentrate by mineral source in metric tons, 2015–2019. Titanium concentrate is mainly obtained from the processing of ilmenite mineral, followed by titaniferous slags and natural rutile.

Titanium is the ninth most abundant element on Earth and represents about 0.6 percent of the Earth's crust. Ilmenite is commonly processed to obtain a titanium concentrate, which is called "synthetic rutile" if it contains more than 90 percent TiO₂, or more generally "titaniferous slags" if it has a lower TiO₂ content. More than 80 percent of the estimated global production of titanium concentrate is obtained from the processing of ilmenite, while 13 percent is obtained from titaniferous slags and 5 percent from rutile.<ref name=":0">{{Cite web |title=Patent Landscape Report |url=https://www.wipo.int/publications/en/details.jsp?id=4651&plang=EN |access-date=2023-10-19 |website=WIPO |doi=10.34667/tind.47029 |language=en |author1=World Intellectual Property Organization. |series=Patent Landscape Reports |date=2023 }}</ref>

Ilmenite can be converted into pigment-grade titanium dioxide via either the sulfate process or the chloride process.<ref name="Ullmann">{{Ullmann|author=Völz, Hans G. |display-authors=etal |title=Pigments, Inorganic|year=2006|doi=10.1002/14356007.a20_243.pub2}}</ref> Ilmenite can also be improved and purified to titanium dioxide in the form of rutile using the Becher process.<ref>{{cite journal |last1=Welham |first1=N.J. |title=A parametric study of the mechanically activated carbothermic reduction of ilmenite |journal=Minerals Engineering |date=December 1996 |volume=9 |issue=12 |pages=1189–1200 |doi=10.1016/S0892-6875(96)00115-X|bibcode=1996MiEng...9.1189W }}</ref>

Ilmenite ores can also be converted to liquid iron and a titanium-rich slag using a smelting process.<ref>{{citation| url = https://www.saimm.co.za/Journal/v108n01p035.pdf | title = Ilmenite smelting: the basics| first = P.C. |last = Pistorius | journal = The Journal of the South African Institute of Mining and Metallurgy | volume = 108 | date = Jan 2008 }}</ref>

Steelmakers use ilmenite ore as a flux to line the blast furnace hearth refractory.<ref name="RTFT Products">{{cite web|title=Rio Tinto, Fer et Titane - Products|url=http://www.rtft.com/ENC/index_ourproducts.asp|publisher=Rio Tinto Group|access-date=19 Aug 2012|archive-date=6 May 2015|archive-url=https://web.archive.org/web/20150506221657/http://www.rtft.com/ENC/index_ourproducts.asp|url-status=dead}}</ref>

Ilmenite can be used to produce ferrotitanium via an aluminothermic reduction.<ref name="FerroAlloy">{{cite book |title=Handbook of Ferroalloys: Theory and Technology |publisher=Elsevier |editor-last1=Gasik |editor-first1=Michael |year=2013 |location=London |pages=429 |isbn=978-0-08-097753-9}}</ref>

== Feedstock production == {| class="wikitable" style="float:right; clear:right; margin:0 0 .5em 1em;" |+Various ilmenite feedstock grades.<ref>{{citation|last=Hayes|year=2011|first=Tony|title=Titanium Dioxide: A Shining Future Ahead|url=http://argex.ca/documents/Euro_Pacific_Canada_Titanium_Dioxide_August2011.pdf|publisher=Euro Pacific Canada|access-date=16 Aug 2012|page=5}}{{dead link|date=August 2018}}</ref> |- ! Feedstock || {{Chem|Ti||O|2}} Content || Process |- ! || (%) || |- | Ore || <55 || Sulfate |- | Ore || >55 || Chloride |- | Ore || <50 || Smelting (slag) |- | Synthetic rutile || 88–95 || Chloride |- | Chloride slag || 85–95 || Chloride |- | Sulfate slag || 80 || Sulfate |} {| class="wikitable" style="float:right; clear:right; margin:0 0 .5em 1em;" |+Estimated contained {{Chem|Ti||O|2}}. <br> production{{sfn|Hayes|2011|p=5}}<ref>USGS 2012 Survey, p. 174</ref><br><small>(Metric tpa x 1,000,</small><br><small>ilmenite & rutile)</small> |- ! Year || 2011 || 2012–13 |- ! Country || USGS || Projected |- | Australia || 1,300 || 247 |- | South Africa || 1,161 || 190 |- | Mozambique || 516 || 250 |- | Canada|| 700|| |- | India || 574|| |- | China || 500|| |- | Vietnam || 490|| |- | Ukraine || 357|| |- | Senegal || - || 330 |- | Norway || 300|| |- | United States || 300|| |- | Madagascar || 288|| |- | Kenya || - || 246 |- | Sri Lanka || 62 || |- | Sierra Leone || 60|| |- | Brazil || 48|| |- | Other countries || 37|| |- | Total world || ~6,700 || ~1,250 |}

Most ilmenite is recovered from heavy mineral sands ore deposits, where the mineral is concentrated as a placer deposit and weathering reduces its iron content, increasing the percentage of titanium. However, ilmenite can also be recovered from "hard rock" titanium ore sources, such as ultramafic to mafic layered intrusions or anorthosite massifs. The ilmenite in layered intrusions is sometimes abundant, but it contains considerable intergrowths of magnetite that reduce its ore grade. Ilmenite from anorthosite massifs often contains large amounts of calcium or magnesium that render it unsuitable for the chloride process.<ref>{{cite book |last1=Murphy |first1=Philip |last2=Frick |first2=Louise |title=Industrial minerals & rocks: commodities, markets, and uses |date=2006 |publisher=Society for Mining, Metallurgy, and Exploration |location=Littleton, Colo. |isbn=9780873352338 |pages=990–991 |edition=7th |url=https://books.google.com/books?id=zNicdkuulE4C |access-date=23 February 2022 |chapter=Titanium |editor-first1=James M. |editor-last1=Barker |editor-first2=Jessica Elzea |editor-last2=Kogel |editor-first3=Nikhil C. |editor-last3=Trivedi |editor-first4=Stanley T. |editor-last4=Krukowski}}</ref>

The proven reserves of ilmenite and rutile ores are estimated to be between 423 and 600 million tonnes of titanium dioxide. The largest ilmenite deposits are in South Africa, India, the United States, Canada, Norway, Australia, Ukraine, Russia and Kazakhstan. Additional deposits are found in Bangladesh, Chile, Mexico and New Zealand.<ref>{{cite book |last1=Güther |first1=V. |last2=Sibum |first2=H. |last3=Roidl |first3=O. |last4=Habashi |first4=F. |last5=Wolf |first5=H |year= 2005 |chapter=Titanium, Titanium Alloys, and Titanium Compounds |title=Ullmann's Encyclopedia of Industrial Chemistry |publisher=Wiley InterScience |isbn=978-3-527-30673-2}}</ref>

Australia was the world's largest ilmenite ore producer in 2011, with about 1.3 million tonnes of production, followed by South Africa, Canada, Mozambique, India, China, Vietnam, Ukraine, Norway, Madagascar and the United States.

The top four ilmenite and rutile feedstock producers in 2010 were Rio Tinto Group, Iluka Resources, Exxaro and Kenmare Resources, which collectively accounted for more than 60% of the world's supplies.{{sfn|Hayes|2011|p=3}}

The world's two largest open cast ilmenite mines are: * The Tellnes mine located in Sokndal Municipality, Norway, and run by Titania AS (owned by Kronos Worldwide Inc.) with 0.55 Mtpa capacity and 57 Mt contained {{Chem|Ti||O|2}} reserves. * The Rio Tinto Group's Lac Tio mine located near Havre Saint-Pierre, Quebec, in Canada with a 3 Mtpa capacity and 52 Mt reserves.<ref name="Lac Tio Page">{{cite web|title=Lac Tio Mine|url=https://www.infomine.com/minesite/minesite.asp?site=lactio|publisher=InfoMine|access-date=16 Aug 2012}}</ref>

Major mineral sands-based ilmenite mining operations include: * Richards Bay Minerals in South Africa, majority-owned by the Rio Tinto Group. * Kenmare Resources' Moma mine in Mozambique. * Iluka Resources' mining operations in Australia, including Murray Basin, Eneabba and Capel. * The Kerala Minerals & Metals Ltd (KMML), Indian Rare Earths (IRE), VV Mineral mines in India. * TiZir Ltd.'s Grande Cote mine in Senegal<ref name="MDL Website">{{cite web|title=TiZir Limited|url=http://www.mineraldeposits.com.au/tizir/|publisher=Mineral Deposits Limited|access-date=16 Aug 2012|url-status=dead|archive-url=https://web.archive.org/web/20120818182108/http://www.mineraldeposits.com.au/tizir/|archive-date=2012-08-18}}</ref> * QIT Madagascar Minerals mine, majority-owned by the Rio Tinto Group, which began production in 2009 and is expected to produce 0.75 Mtpa of ilmenite, potentially expanding to 2 Mtpa in future phases.

Attractive major potential ilmenite deposits include: * The Karhujupukka magnetite-ilmenite deposit in Kolari, northern Finland, with around 5 Mt reserves and ore containing about 6.2% titanium. * The Balla Balla magnetite-iron-titanium-vanadium ore deposit in the Pilbara of Western Australia, which contains 456 million tonnes of cumulate ore horizon grading 45% {{Chem|Fe}}, 13.7% {{Chem|Ti||O|2}} and 0.64% {{Chem|V|2|O|5}}, one of the richest magnetite-ilmenite ore bodies in Australia<ref>{{Cite web | url=http://www.australianminesatlas.gov.au/aimr/commodity/vanadium.html |title = Vanadium – AIMR 2011 – Australian Mines Atlas}}</ref> * The Coburn, WIM 50, Douglas, Pooncarie mineral sands deposits in Australia. * The Magpie titano-magnetite (iron-titanium-vanadium-chrome) deposits in eastern Quebec of Canada with about 1 billion tonnes containing about 43% Fe, 12% TiO₂, 0.4% V₂O₅, and 2.2% Cr₂O₃. * The Longnose deposit in Northeast Minnesota is considered to be "the largest and richest ilmenite deposit in North America."<ref>{{Cite news|url=https://www.mprnews.org/story/2017/05/26/titanium-range-breakthrough-could-lead-to-new-kind-of-mining-in-ne-minn-|title=Titanium Range? Breakthrough could lead to new kind of mining in NE Minn.|last=Kraker|first=Dan|access-date=2017-05-31}}</ref>

thumb|Worldwide mining of the titanium-containing minerals ilmenite and rutile in thousand tonnes of TiO₂ equivalent by country, in 2020.

In 2020, China had by far the highest titanium mining activity. About 35 percent of the world's ilmenite is mined in China, representing 33 percent of total titanium mineral mining (including ilmenite and rutile). South Africa and Mozambique are also important contributors, representing 13 percent and 12 percent of worldwide ilmenite mining, respectively. Australia represents 6 percent of the total ilmenite mining and 31 percent of rutile mining. Sierra Leone and Ukraine are also big contributors to rutile mining.<ref name=":0" />

China is the biggest producer of titanium dioxide, followed by the United States and Germany. China is also a leader in titanium metal production, but Japan, the Russian Federation, and Kazakhstan have emerged as significant contributors to this field.

== Patenting activities == thumb| Patent activity on titanium dioxide production from ilmenite has increased since 2012. Patenting activity related to titanium dioxide production from ilmenite is rapidly increasing.<ref name=":0" /> Between 2002 and 2022, there have been 459 patent families that describe the production of titanium dioxide from ilmenite, and this number is growing rapidly. The majority of these patents describe pre-treatment processes, such as smelting and magnetic separation, to increase the titanium concentration in low-grade ores, resulting in titanium concentrates or slags. Other patents describe processes for obtaining titanium dioxide, either through a direct hydrometallurgical process or via two industrially exploited processes: the sulfate process and the chloride process.

Acid leaching might be used either as a pre-treatment or as part of a hydrometallurgical process to directly obtain titanium dioxide or synthetic rutile (>90 percent titanium dioxide, TiO₂). The sulfate process represents 40 percent of the world's titanium dioxide production and is protected in 23 percent of patent families. The chloride process is only mentioned in 8 percent of patent families, although it provides 60 percent of the worldwide industrial production of titanium dioxide.<ref name=":0" /><br>

Key contributors to patents on the production of titanium dioxide are companies from China, Australia and the United States, reflecting the major contribution of these countries to industrial production. Chinese companies Pangang and Lomon Billions Groups are the main contributors and hold diversified patent portfolios covering both pre-treatment and the processes leading to a final product.

In comparison, patenting activity related to titanium metal production from ilmenite remains stable.<ref name=":0" /> Between 2002 and 2022, there have been 92 patent families that describe the production of titanium metal from ilmenite, and this number has remained relatively steady. These patents describe the production of titanium metal starting from mineral ores, such as ilmenite, and from titanium dioxide (TiO₂) and titanium tetrachloride (TiCl₄), a chemical obtained as an intermediate in the chloride process. The starting materials are purified, if necessary, and then converted to titanium metal through a chemical reduction process using a reducing agent. Processes mainly differ regarding the reducing agent used to transform the starting material into titanium metal: magnesium is the most frequently cited reducing agent and the most exploited in industrial production.<br>

Key players in the field are Japanese companies, in particular Toho Titanium and Osaka Titanium Technologies, both focusing on reduction using magnesium. Pangang also contributes to titanium metal production and holds patents describing reduction by molten salt electrolysis.<ref name=":0" />

== Lunar ilmenite == Ilmenite has been found in lunar samples, particularly in high-Ti lunar mare basalts common from Apollo 11 and Apollo 17 sites, and on average, constitutes up to 5% of lunar meteorites.<ref>Korotev, Randy. 2005 "Lunar geochemistry as told by lunar meteorites." Geochemistry. Vol 65. Pages 297–346. https://doi.org/10.1016/j.chemer.2005.07.001</ref> Ilmenite has been targeted for ISRU water and oxygen extraction due to a simplistic reduction reaction which occurs with CO and H₂ buffers.<ref>Schluter & Cowley. "Review of techniques for in-situ oxygen extraction on the moon." Planetary and Space Science. Vol 181. https://doi.org/10.1016/j.pss.2019.104753</ref><ref>Perreault & Patience. "Ilmenite–CO reduction kinetics." Fuel. Vol 165, 166–172. https://doi.org/10.1016/j.fuel.2015.10.066</ref><ref>Muscatello, Tony. 2017. "Oxygen Extraction from Minerals" Presentation, NASA KSC Applied Chem lab. https://ntrs.nasa.gov/api/citations/20170001458/downloads/20170001458.pdf</ref> The European Space Agency's VMMO mission, expected to launch in 2028, intends to map the distribution of ilmenite on the Moon.<ref>{{Cite web |title=VMMO |url=https://www.esa.int/Enabling_Support/Space_Engineering_Technology/Technology_CubeSats/VMMO |access-date=2025-08-26 |website=www.esa.int |language=en}}</ref><ref>{{Cite web |last=Gao |first=Yang |date=2019-08-29 |title=Building a moon base is a huge task – here are the tiny satellites that will pave the way |url=http://theconversation.com/building-a-moon-base-is-a-huge-task-here-are-the-tiny-satellites-that-will-pave-the-way-121581 |access-date=2025-08-26 |website=The Conversation |language=en-US}}</ref>

== Sources == {{Free-content attribution | title = Production of titanium and titanium dioxide from ilmenite and related applications | publisher = WIPO | documentURL = https://www.wipo.int/edocs/pubdocs/en/wipo-pub-1077-23-en-patent-landscape-report-ilmenite.pdf | license = CC-BY }}

== References == {{Reflist}}

{{Titanium minerals}} {{Titanium compounds}} {{Ores}} {{iron compounds}} {{Authority control}}

Category:Iron(II) minerals Category:Titanium minerals Category:Oxide minerals Category:Ilmenite group Category:Trigonal minerals Category:Minerals in space group 148 Category:Magnetic minerals