Ilmenite
Ilmenite, Fe2+Ti4+O3, is the iron-black titanium oxide: hexagonal, hardness 5 to 6, density 4.72, weakly magnetic. Ideal ilmenite is 31.55% titanium by mass.
Ilmenite is iron titanium oxide, Fe2+Ti4+O3 on the IMA list (G, 1827, Russia): hexagonal, iron-black, hardness 5 to 6, density 4.72, weakly magnetic, with a black to reddish brown streak. Ideal ilmenite is 31.55% titanium and 36.81% iron by mass, and USGS says ilmenite accounts for about 90% of world titanium-mineral consumption.
In short
- The Ti–Fe ledger. Worked on standard atomic weights, FeTiO3 is 31.55% titanium and 36.81% iron, or 52.64% TiO2 and 47.36% FeO; the Handbook of Mineralogy sheet’s ideal column prints 52.65 and 47.35. Its Marcy massif analysis, Adirondacks, has 52.61 wt% TiO2, 31.53% Ti, 99.9% of ideal. Rutile is 59.93% titanium and ulvöspinel, TiFe2O4, 21.41%.
- The A-site reading. The ilmenite-group partners share TiO3 and differ on the other cation: Fe2+ in ilmenite, Mg in geikielite, Mn2+ in pyrophanite, Zn in ecandrewsite. the IMA commission’s 1998 guidelines name a species by the atom filling at least 50% of a site. The Marcy analysis, (Fe2+0.88Mg0.08Fe3+0.04Mn0.01)Ti0.98O3, has 87.1% Fe2+ on that site: ilmenite. The geikielite sheet’s Bergell analysis has 59.4% Mg: geikielite.
- Three FeTiO3 rows. A field scan of the September 2026 IMA-CNMNC Master List, checked by a token scan, finds 12 rows whose formula ends in TiO3 or Ti4+O3. Three are iron and titanium alone: ilmenite (G, 1827, Russia), liuite (A, 2017-042a, India, meteorite) and wangdaodeite (A, 2016-007, China). FeTiO3 on a label names a composition; ilmenite names the species.
- Documented failure: the streak. The sheet gives ilmenite’s streak as black to reddish brown; the hematite sheet gives cherry-red or reddish brown. Both can print reddish brown. Weight separates them: a 20.00 g piece reads 15.76 g in water as ilmenite and 16.20 g as hematite, 0.44 g apart, and 16.14 g as magnetite. Ulvöspinel’s calculated density gives 15.82 g, less than 0.1 g from ilmenite.
- Where. The Distribution field names the Vishnevy-Il’men Mountains, Southern Urals, for large crystals; the Lovozero massif, Kola; Tellnes, Snarum, Kragerø and Arendal, Norway; Binntal, Switzerland; St. Cristophe, Bourg d’Oisans, France; the Lake Sanford area, New York; Allard Lake, Quebec; Bancroft, Ontario; and Arkaroola Bore, South Australia.
| Name | Formula (IMA) | IMA status | System | Hardness | Density | 20.00 g piece in water | Streak (sheet) | Ti by mass | Fe by mass | Magnetism (sheet) |
|---|---|---|---|---|---|---|---|---|---|---|
| Ilmenite | Fe2+Ti4+O3 | G, 1827, Russia | Hexagonal | 5–6 | 4.72 | 15.76 g | Black to reddish brown | 31.55% | 36.81% | Weakly magnetic |
| Geikielite | MgTiO3 | G, 1893, Sri Lanka | Hexagonal | 5–6 | 3.79–4.2 | 14.72–15.24 g | Purplish brown | 39.83% | 0% | None printed |
| Pyrophanite | Mn2+TiO3 | G, 1890, Sweden | Hexagonal | 5–6 | 4.537 | 15.59 g | Ocher-yellow, with greenish tinge | 31.74% | 0% | None printed |
| Ecandrewsite | ZnTiO3; Handbook (Zn,Fe2+,Mn2+)TiO3 | A, 1978-082, Australia | Hexagonal | n.d. (VHN 500–600) | n.d.; calc. 4.98–4.99 | 15.98–15.99 g (calc.) | Dark brown to black | 29.69% | 0% | None printed |
| Hematite | Fe2O3 | A, 1971 s.p. | Hexagonal | 5–6 | 5.26 | 16.20 g | Cherry-red or reddish brown | 0% | 69.94% | None printed |
| Magnetite | Fe2+Fe3+2O4 | G, 1845 | Cubic | 5.5–6.5 | 5.175 | 16.14 g | Black | 0% | 72.36% | Strongly magnetic |
| Ulvöspinel | TiFe2+2O4 | G, 1953, Sweden | Cubic | n.d. (VHN about 650) | n.d.; calc. 4.78 | 15.82 g (calc.) | Not printed | 21.41% | 49.96% | None printed |
| Rutile | TiO2 | G, 1803, Spain | Tetragonal | 6–6.5 | 4.23 | 15.27 g | Pale brown, yellowish brown | 59.93% | 0% | None printed |
What is ilmenite? The iron titanium oxide
Ilmenite is iron titanium oxide, FeTiO3, an iron-black, weakly magnetic mineral of the ilmenite group. The Handbook of Mineralogy ilmenite sheet gives hexagonal, point group −3, as thick tabular crystals with a dominant base, to rhombohedral, to 25 cm, and as skeletal, granular or massive material and lamellar exsolutions in hematite or magnetite. Twinning is simple on {0001} and lamellar on {10-11}; it shows partings, not true cleavage, on {0001} and {10-11}. It is brittle, hardness 5 to 6, Vickers 566 to 698 at a 100 g load, measured density 4.72 against a calculated 4.789, and the sheet prints weakly magnetic.
Colour and optics. Iron-black, gray with a brownish tint in reflected light; streak black to reddish brown; lustre metallic to submetallic. It is opaque, uniaxial (−), strongly anisotropic in shades of gray. What weakly magnetic means on a laboratory separator, with USGS figures, is on is ilmenite magnetic.
What the IMA list records. The September 2026 list gives ilmenite Fe2+Ti4+O3, status G (grandfathered, described before the IMA existed), 1827, with Russia as the country of first description; the sheet writes Fe2+TiO3 and names it for the early-noted occurrence in the Il’men Mountains. Its occurrence line: a common accessory mineral in igneous rocks such as granites, gabbros and kimberlites, in granite pegmatites, carbonatites and high-grade metamorphic rocks, reaching economic concentration in layered mafic intrusions and in black sand placer deposits. Its associates are magnetite, hematite, rutile, ulvöspinel, pyrrhotite and apatite.
How much titanium is in ilmenite? The Ti–Fe ledger
Ideal ilmenite is 31.55% titanium and 36.81% iron by mass. Worked on standard atomic weights (Fe 55.845, Ti 47.867, O 15.999), FeTiO3 weighs 151.71 g per mole, so titanium is 47.867 / 151.71 and iron 55.845 / 151.71. As oxides that is 52.64% TiO2 and 47.36% FeO; the sheet’s ideal column prints 52.65 and 47.35. Substitute any analysis’s TiO2 in the same ratio, 0.5994 titanium per unit of TiO2.
Worked on the sheet’s analysis. The Marcy massif analysis, Adirondacks, New York, by electron microprobe, has 52.61 wt% TiO2, which is 31.53% titanium, 99.9% of the ideal; with it come 42.77 FeO, 2.22 Fe2O3, 2.30 MgO and 0.46 MnO. On the same scale rutile, TiO2, is 59.93% titanium, the figure on rutile; geikielite 39.83%, pyrophanite 31.74%, ecandrewsite 29.69% and ulvöspinel 21.41%.
Why the ledger matters. USGS Mineral Commodity Summaries 2025, Titanium mineral concentrates says ilmenite accounts for about 90% of the world’s consumption of titanium minerals, and that ilmenite, leucoxene, rutile, slag and synthetic rutile compete as feedstock for titanium dioxide pigment, titanium metal and welding-rod coatings; it names TiO2 pigments as used primarily in paint, paper and plastics. This page uses none of the summary’s market or tonnage figures.
Ilmenite, geikielite or pyrophanite? The A-site reading
Ilmenite is named by ferrous iron on the site beside titanium; magnesium there makes geikielite, manganese pyrophanite and zinc ecandrewsite. The ilmenite sheet says it forms three series, with ecandrewsite, geikielite and pyrophanite, and the IMA list writes them MgTiO3 (G, 1893, Sri Lanka), Mn2+TiO3 (G, 1890, Sweden) and ZnTiO3 (A, 1978-082, Australia). Nickel and Grice 1998, the IMA commission’s procedures and guidelines (Canadian Mineralogist 36, 913) says that where two types of atom share a structural site, the species is defined by the atom comprising at least 50% of it.
Worked on the sheets. The ilmenite sheet’s Marcy analysis is printed as (Fe2+0.88Mg0.08Fe3+0.04Mn0.01)Σ=1.01Ti0.98O3: ferrous iron is 87.1% of the site, magnesium 7.9%, so ilmenite by a wide margin. The geikielite sheet’s Bergell zone analysis, (Mg0.60Fe2+0.35Mn0.03Fe3+0.03)Ti0.98Si0.01O3, has 59.4% magnesium and 34.7% ferrous iron: geikielite, 9.4 points above the line, with more than a third of its site still iron. Substitute any analysis in the same division.
Three rows, one formula. The September 2026 list, scanned by field and by token, has 12 rows whose formula ends in TiO3 or Ti4+O3; perovskite, CaTiO3, is among them. Three are written with iron, titanium and oxygen alone: ilmenite, liuite (A, 2017-042a, India, a meteorite) and wangdaodeite (A, 2016-007, China). The IMA guidelines say minerals of the same composition with topologically different structures are separate species; the list gives liuite and wangdaodeite rows of their own, and this page claims nothing about them beyond that.
Ilmenite or hematite? When the streak fails, and where ilmenite is found
Documented failure: the streak. The ilmenite sheet gives a black to reddish brown streak, the hematite sheet cherry-red or reddish brown, so a reddish brown line on the plate fits both. Hardness does not help either: both sheets print 5 to 6. Weight does: at the sheets’ measured densities a 20.00 g piece reads 15.76 g in water as ilmenite and 16.20 g as hematite, 0.44 g apart, and 16.14 g as magnetite. Rutile, 15.27 g, is 0.49 g lighter. Ulvöspinel, at a calculated 4.78, would read 15.82 g, less than 0.1 g from ilmenite, and its sheet says it occurs as an exsolution in magnetite or in ilmenite. The methods are on how to use a streak plate and how to measure specific gravity at home; the streak-and-magnet sequence for the black iron oxides is on magnetite and is not repeated here.
Where ilmenite is found. The Distribution field: widespread and well crystallised from numerous localities; large crystals in the Vishnevy-Il’men Mountains, Southern Urals, Russia, and from the Lovozero massif, Kola Peninsula; in Norway at Tellnes and Snarum, with large crystals from Kragerø and Arendal; Binntal, Valais, Switzerland; St. Cristophe, Bourg d’Oisans, Isère, France; in the USA at Quincy, Massachusetts, Litchfield, Connecticut, and large crystals from the Lake Sanford area, Essex Co., New York; Allard Lake, Quebec, and Bancroft, Ontario; and Arkaroola Bore and near Bimbowrie, South Australia.
Its neighbours. rutile shares the titanium; hematite and magnetite share the iron and the black colour; titanite is the calcium titanium silicate. How ilmenite answers a magnet, set against those neighbours, is on is ilmenite magnetic. The reference section is at the species index. We hold no catalogue and nothing here is offered for sale; the wanted list is the only commercial route.