Ilmenite

Ilmenite, also known as manaccanite, is a titanium-iron oxide mineral with the idealized formula FeTiO
3
. It is a weakly magnetic black or steel-gray solid. From a commercial perspective, ilmenite is the most important ore of titanium.[4] Ilmenite is the main source of titanium dioxide, which is used in paints, printing inks[5], fabrics, plastics, paper, sunscreen, food and cosmetics.[6]

Ilmenite
Ilmenite-155036
Ilmenite from Miass, Ilmen Mts, Chelyabinsk Oblast', Southern Urals, Urals Region, Russia. 4.5 x 4.3 x 1.5 cm
General
CategoryOxide mineral
Formula
(repeating unit)
iron titanium oxide, FeTiO
3
Strunz classification4.CB.05
Dana classification04.03.05.01
Crystal systemTrigonal
Crystal classRhombohedral (3)
H-M symbol: (3)
Space groupR3
Unit cella = 5.08854(7)
c = 14.0924(3) [Å]: Z = 6
Identification
ColorIron-black; gray with a brownish tint in reflected light
Crystal habitGranular to massive and lamellar exsolutions in hematite or magnetite
Twinning{0001} simple, {1011} lamellar
Cleavageabsent; parting on {0001} and {1011}
FractureConchoidal to subconchoidal
TenacityBrittle
Mohs scale hardness5–6
LusterMetallic to submetallic
StreakBlack
DiaphaneityOpaque
Specific gravity4.70–4.79
Optical propertiesUniaxial (–)
BirefringenceStrong; O = pinkish brown, E = dark brown (bireflectance)
Other characteristicsweakly magnetic
References[1][2][3]
Ilmenite
Crystal structure of ilmenite

Structure and properties

Ilmenite crystallizes in the trigonal system. 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. Containing high spin ferrous centers, ilmenite is paramagnetic.

Ilmenite is commonly recognized in altered igneous rocks by the presence of a white alteration product, the pseudo-mineral leucoxene. Often ilmenites are rimmed with leucoxene, which allows ilmenite to be distinguished from magnetite and other iron-titanium oxides. The example shown in the image at right is typical of leucoxene-rimmed ilmenite.

In reflected light it may be distinguished from magnetite by more pronounced reflection pleochroism and a brown-pink tinge.

Samples of ilmenite exhibit a weak response to a hand magnet.

Discovery

In 1791 William Gregor discovered ilmenite, 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 ilmenite.[7]

Mineral chemistry

Ilmenite-65675
Ilmenite from Froland, Aust-Agder, Norway; 4.1 x 4.1 x 3.8 cm
Ilmenite and hematite under normal light
Ilmenite and hematite under normal light
Ilmenite and hematite under polarized light
Ilmenite and hematite under polarized light

Ilmenite most often contains appreciable quantities of magnesium and manganese and the full chemical formula can be expressed as (Fe,Mg,Mn,Ti)O3. Ilmenite forms a solid solution with geikielite (MgTiO
3
) and pyrophanite (MnTiO
3
) which are magnesian and manganiferous end-members of the solid solution series.

Although there appears evidence of the complete range of mineral chemistries in the (Fe,Mg,Mn,Ti)O3 system naturally occurring on Earth, the vast bulk of ilmenites are restricted to close to the ideal FeTiO
3
composition, with minor mole percentages of Mn and Mg. A key exception is in the ilmenites of kimberlites where the mineral usually contains major amounts of geikielite molecules, and in some highly differentiated felsic rocks ilmenites may contain significant amounts of pyrophanite molecules.

At higher temperatures it has been demonstrated 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. 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.

Altered ilmenite forms the mineral leucoxene, an important source of titanium in heavy mineral sands ore deposits. Leucoxene is a typical component of altered gabbro and diorite and is generally indicative of ilmenite in the unaltered rock.

Paragenesis

Tellnes
Tellnes opencast ilmenite mine, Sokndal, Norway

Ilmenite is a common accessory mineral found in metamorphic and igneous rocks. It is found in large concentrations in layered intrusions where it forms as part of a cumulate layer within the silicate stratigraphy of the intrusion. Ilmenite generally occurs within the pyroxenitic portion of such intrusions (the 'pyroxene-in' level).

Magnesian ilmenite is indicative of kimberlitic paragenesis and forms part of the MARID association of minerals (mica-amphibole-rutile-ilmenite-diopside) assemblage of glimmerite xenoliths. Manganiferous ilmenite is found in granitic rocks and also in carbonatite intrusions where it may also contain anomalous niobium.

Many mafic igneous rocks contain grains of intergrown magnetite and ilmenite, formed by the oxidation of ulvospinel. Ilmenite also occurs as discrete grains, typically with some hematite in solid solution, and complete solid solution exists between the two minerals at temperatures above about 950 °C.

Titanium was identified for the first time by William Gregor in 1791 in ilmenite from the Manaccan valley in Cornwall, southwest England.

Ilmenite is named after the locality of its discovery in the Ilmensky Mountains, near Miass, Russia.

Processing and consumption

Most ilmenite is mined for titanium dioxide production.[8] In 2011, about 47% of the titanium dioxide produced worldwide were based on this material.[9] Ilmenite and/or titanium dioxide are used in the production of Titanium metal.[10][11]

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.[12]

Various ilmenite feedstock grades.[13]
Feedstock TiO
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

Ilmenite can be converted into pigment grade titanium dioxide via either the sulfate process or the chloride process.

Ilmenite can also be improved and purified to Rutile using the Becher process.

Ilmenite ores can also be converted to liquid iron and a titanium rich slag using a smelting process.[14]

Ilmenite ore is used as a flux by steelmakers to line blast furnace hearth refractory.[15]

Ilmenite sand is also used as a sandblasting agent in the cleaning of diecasting dies.

Ilmenite can be used to produce ferrotitanium via an aluminothermic reduction.[16]

Feedstock production

Estimated contained TiO
2
.
production[13][17]
(Metric tpa x 1,000,
ilmenite & rutile)
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

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 United States.

Although most ilmenite is recovered from heavy mineral sands ore deposits, ilmenite can also be recovered from layered intrusive sources or "hard rock" titanium ore sources.

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 world's supplies.[18]

The world's two largest open cast ilmenite mines are:

  • The Tellnes mine located in Sokndal, Norway, and run by Titania AS (owned by Kronos Worldwide Inc.) with 0.55 Mtpa capacity and 57 Mt contained TiO
    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.[19]

Major mineral sands based ilmenite mining operations include:

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% Fe, 13.7% TiO
    2
    and 0.64% V
    2
    O
    5
    , one of the richest magnetite-ilmenite ore bodies in Australia[21]
  • 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."[22]

Most ilmenite ore production from Canada, South Africa and Norway is destined for titaniferous slag application.

Lunar ilmenite

Ilmenite has been found in Moon rocks,[23] and is typically highly enriched in magnesium similar to the kimberlitic association. In 2005[24] NASA used the Hubble Space Telescope to locate potentially ilmenite-rich locations. This mineral could be essential to an eventual Moon base, as ilmenite would provide a source of iron and titanium for the building of structures and essential oxygen extraction.

References

  1. ^ Webmineral data
  2. ^ Mineral Handbook
  3. ^ Ilmenite on Mindat.org
  4. ^ 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
  5. ^ "Sachtleben RDI-S" (PDF).
  6. ^ "Products". Mineral Commodities Ltd. Retrieved 2016-08-08.
  7. ^ 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, pp. 40–54, 103–119.
  8. ^ "Industry Fundamentals". Mineral Commodities Ltd. Retrieved 2016-08-08.
  9. ^ Market Study Titanium Dioxide, published by Ceresana, February 2013
  10. ^ Kroll, W (1940). "The production of ductile titanium". Transactions of the Electrochemical Society. 78: 35–47. doi:10.1149/1.3071290.
  11. ^ Seki, Ichiro (2017). "Reduction of titanium dioxide to metallic titanium by nitridization and thermal decomposition". Materials Transactions. 58 (3): 361–366. doi:10.2320/matertrans.MK201601.
  12. ^ "Titanium Dioxide Chemical Economics Handbook".
  13. ^ a b Hayes 2011, p. 5.
  14. ^ Pistorius, P.C. (Jan 2008), "Ilmenite smelting: the basics" (PDF), The Journal of the South African Institute of Mining and Metallurgy, 108
  15. ^ "Rio Tinto, Fer et Titane - Products". Rio Tinto Group. Retrieved 19 Aug 2012.
  16. ^ Gasik, Michael (editor) (2013). Handbook of Ferroalloys: Theory and Technology. London: Elsevier. p. 429. ISBN 978-0-08-097753-9.CS1 maint: extra text: authors list (link)
  17. ^ USGS 2012 Survey, p. 174
  18. ^ Hayes 2011, p. 3.
  19. ^ "Lac Tio Mine". InfoMine. Retrieved 16 Aug 2012.
  20. ^ "TiZir Limited". Mineral Deposits Limited. Archived from the original on 2012-08-18. Retrieved 16 Aug 2012.
  21. ^ "Vanadium - AIMR 2011 - Australian Mines Atlas".
  22. ^ Kraker, Dan. "Titanium Range? Breakthrough could lead to new kind of mining in NE Minn". Retrieved 2017-05-31.
  23. ^ Bhanoo, Sindya N. (28 December 2015). "New Type of Rock Is Discovered on Moon". New York Times. Retrieved 29 December 2015.
  24. ^ http://news.bbc.co.uk/1/hi/magazine/4177064.stm How to set up a moonbase. NASA

Sources

Andesite

For the extinct cephalopod genus, see Andesites.

Andesite ( or ) is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and rhyolite, and ranges from 57 to 63% silicon dioxide (SiO2) as illustrated in TAS diagrams. The mineral assemblage is typically dominated by plagioclase plus pyroxene or hornblende. Magnetite, zircon, apatite, ilmenite, biotite, and garnet are common accessory minerals. Alkali feldspar may be present in minor amounts. The quartz-feldspar abundances in andesite and other volcanic rocks are illustrated in QAPF diagrams.

Classification of andesites may be refined according to the most abundant phenocryst. Example: hornblende-phyric andesite, if hornblende is the principal accessory mineral.

Andesite can be considered as the extrusive equivalent of plutonic diorite. Characteristic of subduction zones, andesite represents the dominant rock type in island arcs. The average composition of the continental crust is andesitic. Along with basalts they are a major component of the Martian crust. The name andesite is derived from the Andes mountain range.

Armalcolite

Armalcolite () is a titanium-rich mineral with the chemical formula (Mg,Fe2+)Ti2O5. It was first found at Tranquility Base on the Moon in 1969 and is named for Armstrong, Aldrin and Collins, the three Apollo 11 astronauts. Together with tranquillityite and pyroxferroite, it is one of three new minerals that were discovered on the Moon. Armalcolite was later identified at various locations on Earth and has been synthesized in the laboratory. (Tranquillityite and pyroxferroite were also later found at various locations on Earth). The synthesis requires low pressures, high temperatures and rapid quenching from about 1,000 °C to the ambient temperature. Armalcolite breaks down to a mixture of magnesium-rich ilmenite and rutile at temperatures below 1,000 °C, but the conversion slows down with cooling. Because of this quenching requirement, armalcolite is relatively rare and is usually found in association with ilmenite and rutile, among other minerals.

Basanite

Basanite ( ) is an igneous, volcanic (extrusive) rock with aphanitic to porphyritic texture.

The mineral assembly is usually abundant feldspathoids (nepheline or leucite), plagioclase, and augite, together with olivine and lesser iron-titanium oxides such as ilmenite and magnetite-ulvospinel; minor alkali feldspar may be present, as illustrated by the position of the field for basanite in the QAPF diagram. Clinopyroxene (augite) and olivine are common as phenocrysts and in the matrix. The augite contains significantly greater titanium, aluminium and sodium than that in typical tholeiitic basalt. Quartz is absent, as are orthopyroxene and pigeonite. Chemically, basanites are mafic. They are low in silica (42 to 45% SiO2) and high in alkalis (3 to 5.5% Na2O and K2O) compared to basalt, which typically contains more SiO2, as evident on the diagram used for TAS classification. Nephelinite is yet richer in Na2O plus K2O compared to SiO2.

Basanites occur both on continents and on ocean islands. Together with basalts, they are produced by hotspot volcanism, for example in the Hawaiian Islands, the Comoros Islands and the Canary Islands.

Bauxite

Bauxite is a sedimentary rock with a relatively high aluminium content. It is the world's main source of aluminium. Bauxite consists mostly of the aluminium minerals gibbsite (Al(OH)3), boehmite (γ-AlO(OH)) and diaspore (α-AlO(OH)), mixed with the two iron oxides goethite (FeO(OH)) and haematite (Fe2O3), the aluminium clay mineral kaolinite (Al2Si2O5(OH)) and small amounts of anatase (TiO2) and ilmenite (FeTiO3 or FeO.TiO2).In 1821 the French geologist Pierre Berthier discovered bauxite near the village of Les Baux in Provence, southern France.

Becher process

The Becher Process is an industrial process used to upgrade ilmenite to synthetic rutile.

The mineral, ilmenite, contains 55-65% titanium as TiO2, the rest being iron oxide. The Becher process removes the iron oxide, leaving a residue of synthetic rutile, which is more than 90% TiO2.

Diorite

Diorite ( ) is an intrusive igneous rock composed principally of the silicate minerals plagioclase feldspar (typically andesine), biotite, hornblende, and/or pyroxene. The chemical composition of diorite is intermediate, between that of mafic gabbro and felsic granite. Diorite is usually grey to dark-grey in colour, but it can also be black or bluish-grey, and frequently has a greenish cast. It is distinguished from gabbro on the basis of the composition of the plagioclase species; the plagioclase in diorite is richer in sodium and poorer in calcium. Diorite may contain small amounts of quartz, microcline, and olivine. Zircon, apatite, titanite, magnetite, ilmenite, and sulfides occur as accessory minerals. Minor amounts of muscovite may also be present. Varieties deficient in hornblende and other dark minerals are called leucodiorite. When olivine and more iron-rich augite are present, the rock grades into ferrodiorite, which is transitional to gabbro. The presence of significant quartz makes the rock type quartz-diorite (>5% quartz) or tonalite (>20% quartz), and if orthoclase (potassium feldspar) is present at greater than 10 percent, the rock type grades into monzodiorite or granodiorite. A dioritic rock containing feldspathoid mineral/s and no quartz is termed foid-bearing diorite or foid diorite according to content.

Diorite has a phaneritic, often speckled, texture of coarse grain size and is occasionally porphyritic.

Orbicular diorite shows alternating concentric growth bands of plagioclase and amphibole surrounding a nucleus, within a diorite porphyry matrix.

Diorites may be associated with either granite or gabbro intrusions, into which they may subtly merge. Diorite results from the partial melting of a mafic rock above a subduction zone. It is commonly produced in volcanic arcs, and in cordilleran mountain building, such as in the Andes Mountains, as large batholiths. The extrusive volcanic equivalent rock type is andesite.

Geikielite

Geikielite is a magnesium titanium oxide mineral with formula: MgTiO3. It is a member of the ilmenite group. It crystallizes in the trigonal system forming typically opaque, black to reddish black crystals.

It was first described in 1892 for an occurrence in the Ceylonese gem bearing gravel placers. It was named for Scottish geologist Sir Archibald Geikie (1835–1924). It occurs in metamorphosed impure magnesian limestones, in serpentinite derived from ultramafic rocks, in kimberlites and carbonatites. Associated minerals include rutile, spinel, clinohumite, perovskite, diopside, serpentine, forsterite, brucite, hydrotalcite, chlorite and calcite.

Granodiorite

Granodiorite ( ) is a phaneritic-textured intrusive igneous rock similar to granite, but containing more plagioclase feldspar than orthoclase feldspar. According to the QAPF diagram, granodiorite has a greater than 20% quartz by volume, and between 65% to 90% of the feldspar is plagioclase. A greater amount of plagioclase would designate the rock as tonalite.

Granodiorite is felsic to intermediate in composition. It is the intrusive igneous equivalent of the extrusive igneous dacite. It contains a large amount of sodium (Na) and calcium (Ca) rich plagioclase, potassium feldspar, quartz, and minor amounts of muscovite mica as the lighter colored mineral components. Biotite and amphiboles often in the form of hornblende are more abundant in granodiorite than in granite, giving it a more distinct two-toned or overall darker appearance. Mica may be present in well-formed hexagonal crystals, and hornblende may appear as needle-like crystals. Minor amounts of oxide minerals such as magnetite, ilmenite, and ulvöspinel, as well as some sulfide minerals may also be present.

Hematite

Hematite, also spelled as haematite, is a common iron oxide with the formula Fe2O3 and is widespread in rocks and soils. Hematite crystallizes in the rhombohedral lattice system, and it has the same crystal structure as ilmenite and corundum. Hematite and ilmenite form a complete solid solution at temperatures above 950 °C (1,740 °F).

Hematite is colored black to steel or silver-gray, brown to reddish-brown, or red. It is mined as the main ore of iron. Varieties include kidney ore, martite (pseudomorphs after magnetite), iron rose and specularite (specular hematite). While these forms vary, they all have a rust-red streak. Hematite is harder than pure iron, but much more brittle. Maghemite is a hematite- and magnetite-related oxide mineral.

Large deposits of hematite are found in banded iron formations. Gray hematite is typically found in places that can have still, standing water or mineral hot springs, such as those in Yellowstone National Park in North America. The mineral can precipitate out of water and collect in layers at the bottom of a lake, spring, or other standing water. Hematite can also occur without water, usually as the result of volcanic activity.

Clay-sized hematite crystals can also occur as a secondary mineral formed by weathering processes in soil, and along with other iron oxides or oxyhydroxides such as goethite, is responsible for the red color of many tropical, ancient, or otherwise highly weathered soils.

Iluka Resources

Iluka Resources is an Australian-based resources company, specialising in mineral sands exploration, project development, operations and marketing. Iluka is the largest producer of zircon and titanium dioxide-derived rutile and synthetic rutile globally. Iluka mines heavy mineral sands and separates the concentrate into its individual mineral constituents rutile, ilmenite, and zircon. Some of the ilmenite is then processed into synthetic rutile.

Iluka has operations in the Australian states of Western Australia (Eucla and Perth Basins), South Australia (Jacinth-Ambrosia Mine), Victoria and New South Wales (Murray Basin), the United States (Virginia) and Sierra Leone.

Indian Rare Earths

IREL (India) Limited (Formally Indian Rare Earths Limited) is a government-owned corporation Mini-Ratna Category A, Schedule B Company, in India based in Mumbai. It was incorporated as a private limited company and jointly owned by the Government of India. Government of India took control of IREL in 1963 under the administrative control of Department of Atomic Energy (DAE). It was incorporated with the primary intention of taking up commercial scale processing of monazite sand at its first unit namely Rare Earths Division (RED), Aluva, Kochi for the recovery of thorium.IREL commissioned its largest division called Orissa Sand Complex (OSCOM) at Chhatrapur, Odisha. Today IREL operates these four units along with a corporate office in Mumbai and a unit located in Manavalakurichi of Kanyakumari district. It produces/sells six heavy minerals namely ilmenite, rutile, zircon, monazite, sillimanite, and garnet as well as various value added products. From 1 May 2015 it started commercial operation of Monazite Processing Plant at Orissa to process 10000tpa monazite to produce 11220tpa of rare earth chloride, 13500 tri-sodium phosphate, 26tpa NGADU etc. Similarly High Pure Rare Earth facility also commenced operation to refine pure rare earth compounds.

The Corporate Research Centre is located at Kollam, Kerala and carries out research in the field of value added products from beach sand minerals, undertakes consultancy projects on mineral separation and flow sheet development, carrying out mineral analysis and caters to the needs of internal and external customers.

Kenmare Resources

Kenmare Resources plc is a mining company based in the Republic of Ireland. It is listed on the Irish Stock Exchange and the London Stock Exchange.

Kenmare owns and operates the Moma mine. Moma is the world's largest titanium mineral deposit, located 160 km from the city of Nampula in Mozambique, Africa.

Maghemite

Maghemite (Fe2O3, γ-Fe2O3) is a member of the family of iron oxides. It has the same spinel ferrite structure as magnetite and is also ferrimagnetic.

Maghemite can be considered as an Fe(II)-deficient magnetite with formula where represents a vacancy, A indicates tetrahedral and B octahedral positioning.

Placer deposit

In geology, a placer deposit or placer is an accumulation of valuable minerals formed by gravity separation from a specific source rock during sedimentary processes. The name is from the Spanish word placer, meaning "alluvial sand". Placer mining is an important source of gold, and was the main technique used in the early years of many gold rushes, including the California Gold Rush. Types of placer deposits include alluvium, eluvium, beach placers, and paleoplacers.

Placer materials must be both dense and resistant to weathering processes. To accumulate in placers, mineral particles must be significantly denser than quartz (whose specific gravity is 2.65), as quartz is usually the largest component of sand or gravel. Placer environments typically contain black sand, a conspicuous shiny black mixture of iron oxides, mostly magnetite with variable amounts of ilmenite and hematite. Valuable mineral components often occurring with black sands are monazite, rutile, zircon, chromite, wolframite, and cassiterite.

Slag

Slag is the glass-like by-product left over after a desired metal has been separated (i.e., smelted) from its raw ore. Slag is usually a mixture of metal oxides and silicon dioxide. However, slags can contain metal sulfides and elemental metals. While slags are generally used to remove waste in metal smelting, they can also serve other purposes, such as assisting in the temperature control of the smelting, and minimizing any re-oxidation of the final liquid metal product before the molten metal is removed from the furnace and used to make solid metal. In some smelting processes, such as ilmenite smelting to produce titanium dioxide, the slag is the valuable product instead of the metal.

Titanium

Titanium is a chemical element with the symbol Ti and atomic number 22. It is a lustrous transition metal with a silver color, low density, and high strength. Titanium is resistant to corrosion in sea water, aqua regia, and chlorine.

Titanium was discovered in Cornwall, Great Britain, by William Gregor in 1791 and was named by Martin Heinrich Klaproth after the Titans of Greek mythology. The element occurs within a number of mineral deposits, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere; it is found in almost all living things, as well as bodies of water, rocks, and soils. The metal is extracted from its principal mineral ores by the Kroll and Hunter processes. The most common compound, titanium dioxide, is a popular photocatalyst and is used in the manufacture of white pigments. Other compounds include titanium tetrachloride (TiCl4), a component of smoke screens and catalysts; and titanium trichloride (TiCl3), which is used as a catalyst in the production of polypropylene.Titanium can be alloyed with iron, aluminium, vanadium, and molybdenum, among other elements, to produce strong, lightweight alloys for aerospace (jet engines, missiles, and spacecraft), military, industrial processes (chemicals and petrochemicals, desalination plants, pulp, and paper), automotive, agriculture (farming), medical prostheses, orthopedic implants, dental and endodontic instruments and files, dental implants, sporting goods, jewelry, mobile phones, and other applications.The two most useful properties of the metal are corrosion resistance and strength-to-density ratio, the highest of any metallic element. In its unalloyed condition, titanium is as strong as some steels, but less dense. There are two allotropic forms and five naturally occurring isotopes of this element, 46Ti through 50Ti, with 48Ti being the most abundant (73.8%). Although they have the same number of valence electrons and are in the same group in the periodic table, titanium and zirconium differ in many chemical and physical properties.

Titanium dioxide

Titanium dioxide, also known as titanium(IV) oxide or titania, is the naturally occurring oxide of titanium, chemical formula TiO2. When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. Generally, it is sourced from ilmenite, rutile and anatase. It has a wide range of applications, including paint, sunscreen and food coloring. When used as a food coloring, it has E number E171. World production in 2014 exceeded 9 million metric tons. It has been estimated that titanium dioxide is used in two-thirds of all pigments, and pigments based on the oxide have been valued at $13.2 billion.

Tiwest Joint Venture

The Tiwest Joint Venture was a joint venture between Tronox Western Australia Pty Ltd and subsidiaries of Exxaro Australia Sands Pty Ltd. The Tiwest Joint Venture was a mining and processing company, established in 1988, to extract ilmenite, rutile, leucoxene and zircon from a mineral sands deposit at Cooljarloo, 14 km north of Cataby, Western Australia. As of June 2012, the joint venture was formally dissolved, when Tronox acquired the mineral-sands-related divisions of Exxaro outright.[1]Tiwest's corporate office (sales/marketing/accounting/administration/IT/etc) was located in Bentley, five minutes drive south of the Perth central business district. During the joint-venture phase of operations, from 1988 through 2012, heavy mineral concentrate was trucked from Cooljarloo, 1 hour and 15 minutes south to the Chandala mineral sands processing plant, near Muchea, 70 km north of Perth. The concentrate was then separated in a facility known as a dry mill, using a magnetic separation-process. Ilmenite was further processed on-site into synthetic rutile, which is used by pigment plants to manufacture paints and similar products. Additional minerals, produced as a byproduct of the rutile production process, were sold as-is. Most synthetic rutile from Chandala was then trucked to Kwinana, 30 km south of Perth, to the Tiwest-owned pigment plant, which produces titanium dioxide a.k.a. TiO2. A $100M upgrade to this Kwinana pigment plant was approved by the boards of both Tronox and Exxaro, and was expected to increase TiO2 pigment production by up to 50% before 2013. TiO2 is the best commercially viable whiting agent known, and is typically used in the manufacture of paints, plastics, and food stuffs.

As part of the 2012 acquisition,[2] the assets of the TIWEST Joint Venture have been folded into the sole parent company, Tronox, which continues to operate in the mineral-sands industry.

Ulvöspinel

Ulvöspinel or ulvite is an iron titanium oxide mineral with formula: Fe2TiO4 or TiFe2+2O4. It forms brown to black metallic isometric crystals with a Mohs hardness of 5.5 to 6. It belongs to the spinel group of minerals, as does magnetite, Fe3O4.

Ulvöspinel forms as solid solutions with magnetite at high temperatures and reducing conditions, and grains crystallized from some basalt-gabbro magmas are rich in the ulvöspinel component. The ulvöspinel component tends to oxidize to magnetite plus ilmenite during subsolidus cooling of the host rocks, and the ilmenite so produced may form apparent exsolution (trellis type) laminae in magnetite. The texture was once interpreted as indicating solid solution between ilmenite and magnetite, until the oxidation reaction and resultant textures were reproduced in laboratory experiments first described by Buddington and Lindsley (1964, Journal of Petrology 5, p. 310-357). The results are important to plate tectonics because magnetite is an important recorder of rock magnetism.

Ulvöspinel was first described by Fredrik Mogensen (1904-1978) from a dolerite layered intrusion in the Ulvö Islands, Ångermanland, Sweden in 1943. The locality is an iron, titanium and vanadium mining area that has been active since the 17th century. It is common in titaniferous magnetite iron ore deposits. It also occurs in kimberlites, in some reduced iron-bearing basalts and is common in lunar basalts.

Titanium minerals
Oxide minerals
Silicate minerals
Other
Titanium compounds
Titanium(II)
Titanium(III)
Titanium(IV)
Ore minerals, mineral mixtures and ore deposits
Ores
Deposit types
Iron compounds
Fe(-II)
Fe(0)
Fe(I)
Fe(0,II)
Fe(II)
Fe(0,III)
Fe(II,III)
Fe(III)
Fe(VI)

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