Ilmenite
FeTiO3 (idealized) · trigonal, R3 (no. 148)
Ilmenite (FeTiO3) is an iron-titanium oxide mineral with a trigonal crystal structure.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Density
4.7 to 4.79 -
Melting
1710 °C
Hardness
5 to 6 Mohs
Oxygen
1.1 wt%
Recipe, share of the weight
- Fe not statedIron
- Ti not statedTitanium
- O not statedOxygen
Best for
Titanium and TiO2 feedstock (more than 80 percent of titanium concentrate comes from ilmenite, per Wikipedia), and the lunar oxygen research case
Weakest at
The 1.10 wt% oxygen yield is an apparent figure from one arXiv paper, and that paper does not state the temperature for it in the text read; no lunar sample or flight data are in this profile
Risk at a glance
- People None found. Three supplier SDS sheets disagree on classification
- If it fails High. Low oxygen yield from highland and polar regolith with little ilmenite
- Corrosion No data. No corrosion data recorded
Quick facts: Ilmenite
| Property | Value | Basis |
|---|---|---|
| Density | 4.7 to 4.79 | 1 sourced value |
| Melting point | 1,710 °C | 1 sourced value |
What is the density of Ilmenite?
Ilmenite has a density of 4.7 to 4.79. The source and test conditions are listed in the properties table on this page.
What is the melting point of Ilmenite?
Ilmenite has a melting point of 1,710 °C. The source and test conditions are listed in the properties table on this page.
What is Ilmenite used for?
Uses recorded in the sources include Lunar in-situ oxygen extraction (research concept, not a flight result); Titanium feedstock for titanium metal and TiO2 pigment; Titanium metal in aerospace.
Why it exists
Ilmenite is an iron-titanium oxide mineral (FeTiO3) and the main titanium mineral concentrate. Wikipedia says lunar ilmenite is a target for water and oxygen extraction by a reduction reaction with CO and H2 buffers. That concept is the reason it is in this collection. The physical data here (density, melting point, hardness) are the ones the sources give; the oxygen yield is reported only as an apparent figure from one arXiv paper.
Where it's used
Titanium and TiO2 feedstock
Wikipedia says more than 80 percent of titanium concentrate comes from ilmenite. USGS reports that in the United States most titanium mineral concentrate is consumed by TiO2 pigment producers.
Aerospace titanium
USGS reports that the majority of titanium metal was used in aerospace applications. The detailed 2025 consumption data were withheld to protect company data.
Lunar oxygen (concept)
Wikipedia describes lunar ilmenite as a target for oxygen extraction by reduction with CO and H2 buffers, and gives no yield. The arXiv paper 2601.14719 gives an apparent yield of 1.10 wt% oxygen under hydrogen reduction, with its temperature not stated in the text read.
Recipe
FeTiO3 (idealized); Fe2+TiO3 (empirical, webmineral)
Ilmenite has the idealized formula FeTiO3: one iron atom, one titanium atom and three oxygen atoms per formula unit. Wikipedia writes the iron as Fe(II). Webmineral gives the empirical form Fe2+TiO3.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Iron Fe | not stated | The redox-active metal. In the lunar concept, reducing the iron oxide is the step that releases oxygen. |
| Titanium Ti | not stated | The main product of the titanium chain. Ilmenite is the largest source of titanium concentrate. |
| Oxygen O | not stated | Bound in the oxide. Reduction with hydrogen or carbon monoxide is the route named for lunar oxygen; an apparent yield of 1.10 wt% is reported by one arXiv paper. |
Weight shares are as printed in the sources.
What it can do
Density
4.7 to 4.79 -
measured
Calculated density is 4.79 gm/cc (webmineral). Wikipedia gives a specific gravity of 4.7 to 4.79 in the infobox.
Melting
1710 °C
measured
Wikipedia gives the liquidus of ilmenite as 1710 °C at a peritectic point.
Hardness
5 to 6 Mohs
measured
Wikipedia gives Mohs hardness 5 to 6 in the infobox and 5.6 to 6 in the text. Webmineral gives 5 to 5.5 on an apatite-knife scale.
Oxygen
1.1 wt%
measured
The arXiv paper 2601.14719 gives an apparent 1.10 wt% oxygen for ilmenite under hydrogen reduction. Prior work it cites reports up to 1-2 wt% oxygen via hydrogen reduction at 900 °C for ilmenite-rich regolith.
How it compares
Ilmenite is a dense, high-melting oxide with a mid-range hardness, and it is the largest source of titanium concentrate. The USGS names rutile, slag and synthetic rutile as alternative feedstocks. We did not read density or melting data for those in this run, so this profile makes no numeric comparison with them.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details.
| Measurement | Ilmenite |
|---|---|
| Thermal behavior and safety | |
| Liquidus temperature (peritectic) | 1710 °C3 |
| Complete ilmenite-hematite solid solution above this temperatureValue printed in the Wikipedia article text | 950 °C |
| TiO2 content of ideal FeTiO3 (analysis column 2) | 52.65 wt%8 |
| Physical and electrical | |
| Calculated density | 4.79 gm/cc1 |
| Specific gravity range | 4.7 to 4.79 -2 |
| Mohs hardness (infobox range)Range printed in the Wikipedia infobox | 5 to 6 -4 |
| Hardness on an apatite-knife scale (not labelled Mohs by the source)Range printed on the webmineral data page | 5 to 5.5 - |
| Vickers hardness (printed as VHN, 100 g load) | 566 to 698 VHN7 |
| Temperature behavior | |
| Hydrogen reduction temperature for ilmenite-rich regolith (cited prior work) | 900 °C10 |
| Other measurements | |
| Molecular weight of Fe2+TiO3 | 151.7 gm5 |
| Calculated refractive index (uniaxial, negative) | 2.42 -6 |
| Hematite (Fe2O3) in natural ilmenite, upper valueValue printed in the Wikipedia article text | < 6 wt% |
| Fe2O3 content of ferrian ilmeniteRange printed in the Wikipedia article text | 6 to 13 percent |
| Apparent oxygen yield under hydrogen reduction | 1.1 wt%9 |
Why choose it, and why not
Good for
- Titanium feedstock. Wikipedia says more than 80 percent of titanium concentrate comes from ilmenite.
- Lunar oxygen research. Wikipedia describes ilmenite as a target for oxygen extraction, and one arXiv paper gives an apparent yield of 1.10 wt% oxygen.
Watch out for
- The Mohs hardness differs between sources: 5 to 6 in the infobox, and 5 to 5.5 on an apatite-knife scale on webmineral.
- The USGS production figures are titanium dioxide content, not the mass of ilmenite mineral.
- The 1.10 wt% oxygen yield is apparent, comes from one paper, and its temperature is not stated in the text read. The lunar highland and south-pole simulants give far lower yields, 0.02 wt% and 0.01 wt%.
Ilmenite is a dense iron-titanium oxide with a high liquidus temperature (1710 °C) and a well-documented titanium supply chain. For oxygen extraction, one arXiv paper gives an apparent yield of 1.10 wt% oxygen, while its lunar simulant results are much lower. Energy and temperature data for a working plant are still missing.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Calculated density | Calculated density printed on the webmineral data page | basis calculated density printed by webmineral (Den(Calc)); the page's specific gravity note also gives 4.79 gm/ccform ideal mineral, Fe2+TiO3 | — |
| 2 | Specific gravity range | Range printed in the Wikipedia infobox (specific gravity is a dimensionless ratio) | basis specific gravity range printed in the Wikipedia infobox; the article text gives specific gravity 4.7form ilmenite mineral | — |
| 3 | Liquidus temperature (peritectic) | Value printed in the Wikipedia infobox, melting point row | basis liquidus temperature at a peritectic point, as printed | — |
| 4 | Mohs hardness (infobox range) | — | basis range printed in the Wikipedia infobox | The Wikipedia text says Mohs hardness 5.6 to 6, which differs from the infobox range 5 to 6 at the low end. Both are shown and neither is reconciled. |
| 5 | Molecular weight of Fe2+TiO3 | Value printed on the webmineral data page as Molecular Weight; the method is not stated | formula Fe2+TiO3 (empirical formula printed by webmineral) | — |
| 6 | Calculated refractive index (uniaxial, negative) | Calculated by the Gladstone-Dale relation as printed on webmineral | basis NCalc from the calculated density using the Gladstone-Dale constant KC 0.2959, as printed by webmineral; the page also gives 2.4 from the measured densityoptics uniaxial (-) | — |
| 7 | Vickers hardness (printed as VHN, 100 g load) | Range printed in the Handbook of Mineralogy physical properties paragraph; unit as printed | basis range printed as VHN = 566-698 at a 100 g load in the physical properties paragraphload 100 g | — |
| 8 | TiO2 content of ideal FeTiO3 (analysis column 2) | Column (2) of the Handbook of Mineralogy chemistry table, labelled FeTiO3 | basis column (2) of the handbook chemistry table, printed as the ideal formula FeTiO3form ideal FeTiO3, not a measured analysis | — |
| 9 | Apparent oxygen yield under hydrogen reduction | Value stated in the results text of the arXiv paper (its own experiment); not a flight result | basis apparent yield printed in the text for ilmenite under hydrogen reduction conditions; the paper calls it apparenttemperature not stated in the text read | — |
| 10 | Hydrogen reduction temperature for ilmenite-rich regolith (cited prior work) | Temperature stated in the arXiv paper, citing earlier work (Sargeant et al. 2020a; Reiss et al. 2019); the profile does not reproduce those experiments | basis temperature at which the paper cites prior hydrogen reduction of ilmenite-rich regolith, given there as up to 1-2 wt% oxygenfeedstock ilmenite-rich regolith | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Natural weathering in placer deposits | not rated | Ilmenite weathers to leucoxene, which is enriched to 70 percent or more TiO2, and weathering lowers its iron content.1 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Natural weathering in placer deposits | Ilmenite alters or weathers to form the pseudo-mineral leucoxene, enriched to 70% or more of TiO2 (Wikipedia). In placer deposits, weathering reduces the iron content and increases the titanium percentage (Wikipedia). | basis natural weathering; the source gives no rate, duration or test conditionproduct leucoxene |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The Teichert SDS lists irritation statements for eyes, skin and the respiratory tract. The Valentine Clays and Pottery Crafts SDS sheets say Not Classified under CLP, and Valentine Clays adds a chronic silica hazard. All three are shown; none is reconciled.
- The powder
- Read the supplier SDS before handling ilmenite powder. Crystalline silica (quartz) is listed as a component in one SDS, and fine particles in air may be ignitable, per that SDS. No GHS H-codes are printed in these sources.
Lunar oxygen concept
The hazards of the reduction gases are not covered by the sources read for this profile.
- Reducing gases
- Wikipedia names CO and H2 as the buffers for the lunar reduction reaction. Their handling risks are not in this record.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Low oxygen yield from highland and polar regolith with little ilmenitehigh severity | Hydrogen reduction of Lunar Highlands Soil or Lunar South Pole simulant, where ilmenite is scarceApparent oxygen yield of about 0.02 wt% for the highland simulant and 0.01 wt% for the south-pole simulant, from temperature-programmed reduction. These are simulant results, not ilmenite. |
| Water, not free oxygen, leaves the reduction step firstmoderate severity | Hydrogen reduction by reaction FeTiO3 + H2 gives Fe + TiO2 + H2OThe paper says water is an intermediate rather than gaseous oxygen directly, and that water electrolysis then liberates breathable O2, so a further step is needed. |
Supply and geography
How common the raw materials are and where they come from.
Ilmenite (titanium mineral concentrate, FeTiO3)
Not found for ilmenite in a USGS source read here. Wikipedia gives titanium at about 0.6 percent of the Earth's crust and as the ninth most abundant element (titanium, not ilmenite alone).
- Top producers (2025)
- China 34%, Mozambique 20.2%, South Africa 13.8%, Australia 8.3%, Canada 3.8%
- Critical mineral lists
- US: listed
- Recycling
- USGS: Recycling: None.
- Substitutes
- USGS: ilmenite, leucoxene, rutile, slag and synthetic rutile compete as feedstock sources for TiO2 pigment, titanium metal and welding-rod coatings.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: ilmenite
spore_version: 0.2
family: iron-titanium-oxide
name: Ilmenite
role: oxygen-extraction feedstock
category: regolith
type: extracted-metals-and-oxygen
summary: |
Ilmenite (FeTiO3) is an iron-titanium oxide mineral with a trigonal crystal structure. Webmineral gives its calculated density as 4.79 gm/cc and its molecular weight as 151.73 gm. Wikipedia gives a liquidus melting point of 1710 °C at a peritectic point, and a Mohs hardness of 5 to 6. Ilmenite is the main titanium mineral concentrate: USGS reports 9,400 thousand metric tons (TiO2 content) of world ilmenite mine production in 2025, with China at about one-third of the total. Lunar ilmenite is named as a target for oxygen extraction; one arXiv paper (2601.14719) gives an apparent yield of 1.10 wt% oxygen under hydrogen reduction. The Handbook of Mineralogy gives a Vickers hardness of 566 to 698 VHN, and its ideal FeTiO3 composition carries 52.65 wt% TiO2.
best_for: Titanium and TiO2 feedstock (more than 80 percent of titanium concentrate comes from ilmenite, per Wikipedia), and the lunar oxygen research case
weakest_at: The 1.10 wt% oxygen yield is an apparent figure from one arXiv paper, and that paper does not state the temperature for it in the text read; no lunar sample or flight data are in this profile
identity:
formula: FeTiO3 (idealized); Fe2+TiO3 (empirical, webmineral)
crystal_system: trigonal
space_group: R3 (no. 148)
source: wikipedia-ilmenite
where: 'Wikipedia infobox: formula FeIITiO3, trigonal, rhombohedral class (3), space group R3 (no. 148), Z = 6, cell a = 5.08854(7) Å and c = 14.0924(3) Å. Webmineral prints a = 5.093 and c = 14.06 with no unit, and the same space group R 3.'
tags:
applications:
- in-space-manufacturing
- structures
properties:
- benchmark: density
label: Calculated density
value: 4.79
unit: gm/cc
scope: material
conditions:
basis: calculated density printed by webmineral (Den(Calc)); the page's specific gravity note also gives 4.79 gm/cc
form: ideal mineral, Fe2+TiO3
method: Calculated density printed on the webmineral data page
status: calculated
source: webmineral-ilmenite
where: Physical Properties, Den(Calc) and specific gravity note
- benchmark: density
label: Specific gravity range
value: 4.7
value_high: 4.79
bound: range
unit: '-'
scope: material
conditions:
basis: specific gravity range printed in the Wikipedia infobox; the article text gives specific gravity 4.7
form: ilmenite mineral
method: Range printed in the Wikipedia infobox (specific gravity is a dimensionless ratio)
status: ground
source: wikipedia-ilmenite
where: Infobox, Specific gravity row
- benchmark: melting_point
label: Liquidus temperature (peritectic)
value: 1710
unit: °C
scope: material
conditions:
basis: liquidus temperature at a peritectic point, as printed
method: Value printed in the Wikipedia infobox, melting point row
status: ground
source: wikipedia-ilmenite
where: Infobox, Melting point row
- benchmark: mohs_hardness
label: Mohs hardness (infobox range)
value: 5
value_high: 6
bound: range
unit: '-'
scope: material
conditions:
basis: range printed in the Wikipedia infobox
method: Range printed in the Wikipedia infobox
status: ground
note: The Wikipedia text says Mohs hardness 5.6 to 6, which differs from the infobox range 5 to 6 at the low end. Both are shown and neither is reconciled.
source: wikipedia-ilmenite
where: Infobox, Mohs hardness row; Structure and properties section
- benchmark: hardness_apatite_knife
label: Hardness on an apatite-knife scale (not labelled Mohs by the source)
value: 5
value_high: 5.5
bound: range
unit: '-'
scope: material
conditions:
basis: printed as 5-5.5 with the note Apatite-Knife Blade; the page does not label this scale as Mohs
method: Range printed on the webmineral data page
status: ground
source: webmineral-ilmenite
where: Physical Properties, Hardness row
- benchmark: molar_mass
label: Molecular weight of Fe2+TiO3
value: 151.73
unit: gm
scope: material
conditions:
formula: Fe2+TiO3 (empirical formula printed by webmineral)
method: Value printed on the webmineral data page as Molecular Weight; the method is not stated
status: calculated
source: webmineral-ilmenite
where: Chemical data, Molecular Weight row
- benchmark: refractive_index
label: Calculated refractive index (uniaxial, negative)
value: 2.42
unit: '-'
scope: material
conditions:
basis: NCalc from the calculated density using the Gladstone-Dale constant KC 0.2959, as printed by webmineral; the page also gives 2.4 from the measured density
optics: uniaxial (-)
method: Calculated by the Gladstone-Dale relation as printed on webmineral
status: calculated
source: webmineral-ilmenite
where: Optical Data, NCalc row
- benchmark: hematite_content
label: Hematite (Fe2O3) in natural ilmenite, upper value
value: 6
bound: upper
unit: wt%
scope: material
conditions:
basis: upper value printed in the mineral chemistry section; ilmenite with more Fe2O3 is called ferrian ilmenite
method: Value printed in the Wikipedia article text
status: ground
source: wikipedia-ilmenite
where: Mineral chemistry section
- benchmark: ferrian_ilmenite_fe2o3
label: Fe2O3 content of ferrian ilmenite
value: 6
value_high: 13
bound: range
unit: percent
scope: material
conditions:
basis: ilmenite containing 6 to 13 percent Fe2O3 is called ferrian ilmenite
method: Range printed in the Wikipedia article text
status: ground
source: wikipedia-ilmenite
where: Mineral chemistry section
- benchmark: solid_solution_onset_temperature
label: Complete ilmenite-hematite solid solution above this temperature
value: 950
unit: °C
scope: material
conditions:
basis: text says that at temperatures above 950 °C (1,740 °F) there is complete solid solution between ilmenite and hematite
method: Value printed in the Wikipedia article text
status: ground
source: wikipedia-ilmenite
where: Mineral chemistry section
- benchmark: vickers_hardness
label: Vickers hardness (printed as VHN, 100 g load)
value: 566
value_high: 698
bound: range
unit: VHN
scope: material
conditions:
basis: range printed as VHN = 566-698 at a 100 g load in the physical properties paragraph
load: 100 g
method: Range printed in the Handbook of Mineralogy physical properties paragraph; unit as printed
status: ground
source: handbook-mineralogy-ilmenite
where: Physical Properties paragraph, Hardness = 5-6 VHN = 566-698 (100 g load)
- benchmark: tio2_content
label: TiO2 content of ideal FeTiO3 (analysis column 2)
value: 52.65
unit: wt%
scope: material
conditions:
basis: column (2) of the handbook chemistry table, printed as the ideal formula FeTiO3
form: ideal FeTiO3, not a measured analysis
method: Column (2) of the Handbook of Mineralogy chemistry table, labelled FeTiO3
status: calculated
source: handbook-mineralogy-ilmenite
where: Chemistry table, TiO2 row, column (2)
- benchmark: hydrogen_reduction_oxygen_yield
label: Apparent oxygen yield under hydrogen reduction
value: 1.1
unit: wt%
scope: material
conditions:
basis: apparent yield printed in the text for ilmenite under hydrogen reduction conditions; the paper calls it apparent
temperature: not stated in the text read
method: Value stated in the results text of the arXiv paper (its own experiment); not a flight result
status: ground
source: arxiv-2601-14719
where: Section 3.2.1 Hydrogen TPR Reduction Behavior, paragraph naming ilmenite the most efficient oxygen source
- benchmark: hydrogen_reduction_temperature
label: Hydrogen reduction temperature for ilmenite-rich regolith (cited prior work)
value: 900
unit: °C
scope: material
conditions:
basis: temperature at which the paper cites prior hydrogen reduction of ilmenite-rich regolith, given there as up to 1-2 wt% oxygen
feedstock: ilmenite-rich regolith
method: Temperature stated in the arXiv paper, citing earlier work (Sargeant et al. 2020a; Reiss et al. 2019); the profile does not reproduce those experiments
status: ground
source: arxiv-2601-14719
where: Section 3.2.1 Hydrogen TPR Reduction Behavior, paragraph citing prior work at 900 °C
corrosion:
- environment: Natural weathering in placer deposits
headline: Ilmenite weathers to leucoxene, which is enriched to 70 percent or more TiO2, and weathering lowers its iron content.
effect: Ilmenite alters or weathers to form the pseudo-mineral leucoxene, enriched to 70% or more of TiO2 (Wikipedia). In placer deposits, weathering reduces the iron content and increases the titanium percentage (Wikipedia).
rating: unknown
conditions:
basis: natural weathering; the source gives no rate, duration or test condition
product: leucoxene
source: wikipedia-ilmenite
where: Mineral chemistry paragraph on leucoxene; placer deposit sentence in the same article
risks:
hazards:
- text: 'Teichert SDS (effective 06/01/24) GHS label elements list two hazard statements: May cause irritation of eyes and skin; May cause respiratory irritation. No H-codes are printed.'
ghs: []
source: teichert-sds-ilmenite
where: Section 2, GHS label elements, Hazard Statements list
- text: 'Valentine Clays SDS (EU format, Regulation (EC) 2020/878) classifies ilmenite as Not Classified under CLP, but adds an other hazard: repeated inhalation of crystalline silica dust over time can cause lung disease and cancer.'
ghs: []
source: valentine-sds-ilmenite
where: Section 2.1 Classification and Section 2.3 Other Hazards
- text: Pottery Crafts P3324 SDS gives Not Classified for physical, health and environmental hazards, with hazard statements printed as NC. The three SDS sheets disagree and all are shown.
ghs: []
source: potterycrafts-msds-ilmenite
where: Section 2.1 Classification, Hazard statements row
- text: 'Respirable crystalline silica (quartz, CAS 14808-60-7, listed as a component of the Teichert product): prolonged and repeated exposure to high concentrations of respirable silica dust could lead to lung disease including chronic pulmonary obstructive disease and silicosis.'
ghs: []
source: teichert-sds-ilmenite
where: Section 2, Inhalation and Chronic Effects; Section 3 Composition
- text: 'Dust fire and explosion: the Teichert SDS says concentrated suspensions of fine particles in air may be ignitable/explosive.'
ghs: []
source: teichert-sds-ilmenite
where: Section 5 Fire Fighting Measures, Flammable Properties
- text: Naturally occurring radioactive elements of the uranium and thorium series are present at low levels in common ilmenite, per the Valentine Clays SDS.
ghs: []
source: valentine-sds-ilmenite
where: Section 2.3 Other Hazards
failure_risks:
- mode: Low oxygen yield from highland and polar regolith with little ilmenite
trigger: Hydrogen reduction of Lunar Highlands Soil or Lunar South Pole simulant, where ilmenite is scarce
consequence: Apparent oxygen yield of about 0.02 wt% for the highland simulant and 0.01 wt% for the south-pole simulant, from temperature-programmed reduction. These are simulant results, not ilmenite.
severity: high
source: arxiv-2601-14719
where: Section 3.2.1 Hydrogen TPR Reduction Behavior, text on Lunar Highlands Soil and LSP oxygen extraction
- mode: Water, not free oxygen, leaves the reduction step first
trigger: Hydrogen reduction by reaction FeTiO3 + H2 gives Fe + TiO2 + H2O
consequence: The paper says water is an intermediate rather than gaseous oxygen directly, and that water electrolysis then liberates breathable O2, so a further step is needed.
severity: moderate
source: arxiv-2601-14719
where: Reaction (1) in Section 3.2.1; the Results and Discussion paragraph on water as an intermediate after Figure 5
side_effects: []
handling: []
mitigations: []
uses:
- application: in-space-manufacturing
device: Lunar in-situ oxygen extraction (research concept, not a flight result)
example: Wikipedia says ilmenite is targeted for water and oxygen extraction by a reduction reaction with CO and H2 buffers, and gives no yield figure.
source: wikipedia-ilmenite
where: Lunar ilmenite section
- application: structures
device: Titanium feedstock for titanium metal and TiO2 pigment
example: Wikipedia says more than 80 percent of titanium concentrate comes from ilmenite, with the rest from titaniferous slags and rutile.
source: wikipedia-ilmenite
where: Processing and consumption section
- application: structures
device: Titanium metal in aerospace
example: USGS reports that the majority of titanium metal was used in aerospace applications, and withholds the detailed 2025 consumption data.
source: usgs-mcs2026-titanium
where: Domestic Production and Use paragraph
supply:
- subject: Ilmenite (titanium mineral concentrate, FeTiO3)
abundance: Not found for ilmenite in a USGS source read here. Wikipedia gives titanium at about 0.6 percent of the Earth's crust and as the ninth most abundant element (titanium, not ilmenite alone).
producers:
- country: China
share_percent: 34
year: 2025
- country: Mozambique
share_percent: 20.2
year: 2025
- country: South Africa
share_percent: 13.8
year: 2025
- country: Australia
share_percent: 8.3
year: 2025
- country: Canada
share_percent: 3.8
year: 2025
critical_lists:
- list: USGS Final 2025 List of Critical Minerals (titanium listed; ilmenite not listed on its own)
listed: true
recycling: 'USGS: Recycling: None.'
substitutes:
- 'USGS: ilmenite, leucoxene, rutile, slag and synthetic rutile compete as feedstock sources for TiO2 pigment, titanium metal and welding-rod coatings.'
source: usgs-mcs2026-titanium-concentrates
where: World Mine Production and Reserves table, ilmenite rows, 2025 column (data in thousand metric tons, TiO2 content; the world total is 9,400, and the shares are calculated by Space Mushroom against it). World ilmenite reserves printed as more than 490,000 thousand tons (TiO2 content). China share from the Events, Trends and Issues paragraph (about one-third). Recycling and Substitutes sections, pages 199 and 200.
documents:
- title: 'Wikipedia: Ilmenite (article used for composition, mineral chemistry and lunar concept)'
type: database
url: https://en.wikipedia.org/wiki/Ilmenite
year: 2026
- title: 'Webmineral: Ilmenite mineral data'
type: database
url: https://www.webmineral.com/data/Ilmenite.shtml
year: 2026
- title: USGS Mineral Commodity Summaries 2026, Titanium Mineral Concentrates (pages 199 and 200)
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026.pdf
year: 2026
- title: USGS Mineral Commodity Summaries 2026, Titanium and Titanium Dioxide
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-titanium.pdf
year: 2026
- title: Teichert Aggregates Ilmenite SDS (revision 6/1/2024)
type: sds
url: https://teichert.com/wp-content/uploads/Ilmenite-Teichert-SDS-6.2024.pdf
year: 2024
- title: Valentine Clays Ilmenite SDS (EU format, Regulation (EC) No 2020/878)
type: sds
url: https://valentineclays.co.uk/cdn/shop/files/Ilmenite_Safety_Data_Sheet.pdf
- title: Pottery Crafts Ilmenite MSDS (P3324)
type: sds
url: https://potterycrafts.co.uk/cdn/shop/files/P3324_ILMENITE_MSDS_25.pdf
year: 2025
- title: arXiv 2601.14719, Physicochemical properties of lunar regolith simulant for in situ oxygen production
type: paper
url: https://arxiv.org/pdf/2601.14719
year: 2026
- title: Handbook of Mineralogy, Ilmenite
type: report
url: https://www.handbookofmineralogy.org/pdfs/ilmenite.pdf
year: 2005
gaps:
- 'Oxygen yield: the arXiv paper 2601.14719 gives an apparent 1.10 wt% oxygen for ilmenite under hydrogen reduction, but its temperature and sample are not stated in the text read. The reduction rate and the Sargeant et al. (2020) papers in Planetary and Space Science were not opened; their figures seen in search snippets are not used.'
- 'No CAS number is set in identity: PubChem could not be opened. The Teichert SDS prints 12168-52-4 for ilmenite and the Valentine Clays SDS prints 103170-28-1; the two differ, so neither is used as the profile CAS.'
- No corrosion test data for ilmenite were found. Weathering to leucoxene is cited from Wikipedia with no rate, duration or test condition.
- No Curie temperature or magnetic numbers. Webmineral says naturally weak magnetism and Wikipedia says weakly magnetic, with no values.
- No thermal conductivity, specific heat, thermal expansion or elastic modulus were found.
- Measured density printed by webmineral (4.72) has no unit on the page, so it is not used.
- 'Mohs hardness conflicts across sources: Wikipedia infobox 5 to 6, Wikipedia text 5.6 to 6, webmineral 5 to 5.5 on an apatite-knife scale. All are shown and none is reconciled.'
- 'Cell parameters are in identity.where only: Wikipedia prints them in angstroms and webmineral prints them without units.'
- The EU critical raw materials list was not opened in this run, so no EU list entry is given for titanium or ilmenite.
- Atomic weights for iron, titanium and oxygen were not read from a fetched page, so story.recipe gives atom counts only.
- No media (photos or drawings) added for this profile.
- Only 14 sourced properties and 9 sources were reached in this run. The site bar is met, but the lithium standard asks for 15 properties.
- 'Benchmark names not in spores/property-canon.yaml: vickers_hardness, tio2_content, hydrogen_reduction_oxygen_yield, hydrogen_reduction_temperature and hardness_apatite_knife. No canonical name was found for these.'
sources:
wikipedia-ilmenite:
title: Ilmenite
id: Wikipedia article, Ilmenite (en)
url: https://en.wikipedia.org/wiki/Ilmenite
year: 2026
kind: web
license: CC BY-SA 4.0 (Wikipedia)
webmineral-ilmenite:
title: Ilmenite mineral data
id: Webmineral data page
url: https://www.webmineral.com/data/Ilmenite.shtml
year: 2026
kind: database
license: web page, cited not reproduced
usgs-mcs2026-titanium-concentrates:
title: Mineral Commodity Summaries 2026, Titanium Mineral Concentrates (pages 199 and 200 of the compilation)
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-titanium:
title: Mineral Commodity Summaries 2026, Titanium and Titanium Dioxide
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-titanium.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-crit-2025:
title: Mineral Commodity Summaries 2026, Final 2025 List of Critical Minerals (table in the introduction)
id: USGS Final 2025 List of Critical Minerals, published November 7, 2025
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026.pdf
year: 2025
kind: report
license: public domain (USGS)
teichert-sds-ilmenite:
title: Teichert Aggregates, Ilmenite Safety Data Sheet (effective 06/01/24, replaces June 2018)
id: Teichert Aggregates SDS, revision date 6/1/2024
url: https://teichert.com/wp-content/uploads/Ilmenite-Teichert-SDS-6.2024.pdf
year: 2024
kind: datasheet
license: Supplier SDS, cited
valentine-sds-ilmenite:
title: 'Valentine Clays, Safety Data Sheet: Ilmenite (EU format, Regulation (EC) No 2020/878)'
id: Valentine Clays SDS, Ilmenite
url: https://valentineclays.co.uk/cdn/shop/files/Ilmenite_Safety_Data_Sheet.pdf
kind: datasheet
license: Supplier SDS, cited
potterycrafts-msds-ilmenite:
title: Pottery Crafts, Ilmenite MSDS (product P3324)
id: Potterycrafts P3324 ILMENITE MSDS
url: https://potterycrafts.co.uk/cdn/shop/files/P3324_ILMENITE_MSDS_25.pdf
year: 2025
kind: datasheet
license: Supplier SDS, cited
arxiv-2601-14719:
title: Physicochemical properties of lunar regolith simulant for in situ oxygen production
id: arXiv:2601.14719v1
url: https://arxiv.org/pdf/2601.14719
year: 2026
kind: paper
license: arXiv, cited
handbook-mineralogy-ilmenite:
title: Handbook of Mineralogy, Ilmenite (Mineral Data Publishing)
id: Handbook of Mineralogy, version 1, c 2001-2005
url: https://www.handbookofmineralogy.org/pdfs/ilmenite.pdf
year: 2005
kind: handbook
license: Mineral Data Publishing, cited
license: CC-BY-4.0
updated: '2026-11-02'
review:
status: draft
method: assistant
checked_values: 14
unreachable: 2
caveats: 4
note: Written by an assistant on 2026-11-01 from five fetched sources; deepened on 2026-11-02 with the Teichert, Valentine Clays and Pottery Crafts SDS sheets, the arXiv 2601.14719 paper and the Handbook of Mineralogy entry, all read in this run. Fourteen values are checked. PubChem could not be opened, and the Sargeant 2020 papers were not reached.
story:
recipe:
line: 'Ilmenite has the idealized formula FeTiO3: one iron atom, one titanium atom and three oxygen atoms per formula unit. Wikipedia writes the iron as Fe(II). Webmineral gives the empirical form Fe2+TiO3.'
parts:
- name: Iron
symbol: Fe
role: The redox-active metal. In the lunar concept, reducing the iron oxide is the step that releases oxygen.
- name: Titanium
symbol: Ti
role: The main product of the titanium chain. Ilmenite is the largest source of titanium concentrate.
- name: Oxygen
symbol: O
role: Bound in the oxide. Reduction with hydrogen or carbon monoxide is the route named for lunar oxygen; an apparent yield of 1.10 wt% is reported by one arXiv paper.
risk_groups:
- title: For people
level: 0
verdict: Three supplier SDS sheets disagree on classification
lead: The Teichert SDS lists irritation statements for eyes, skin and the respiratory tract. The Valentine Clays and Pottery Crafts SDS sheets say Not Classified under CLP, and Valentine Clays adds a chronic silica hazard. All three are shown; none is reconciled.
points:
- label: The powder
line: Read the supplier SDS before handling ilmenite powder. Crystalline silica (quartz) is listed as a component in one SDS, and fine particles in air may be ignitable, per that SDS. No GHS H-codes are printed in these sources.
- title: Lunar oxygen concept
lead: The hazards of the reduction gases are not covered by the sources read for this profile.
points:
- label: Reducing gases
line: Wikipedia names CO and H2 as the buffers for the lunar reduction reaction. Their handling risks are not in this record.
why: Ilmenite is an iron-titanium oxide mineral (FeTiO3) and the main titanium mineral concentrate. Wikipedia says lunar ilmenite is a target for water and oxygen extraction by a reduction reaction with CO and H2 buffers. That concept is the reason it is in this collection. The physical data here (density, melting point, hardness) are the ones the sources give; the oxygen yield is reported only as an apparent figure from one arXiv paper.
uses:
- where: Titanium and TiO2 feedstock
line: Wikipedia says more than 80 percent of titanium concentrate comes from ilmenite. USGS reports that in the United States most titanium mineral concentrate is consumed by TiO2 pigment producers.
- where: Aerospace titanium
line: USGS reports that the majority of titanium metal was used in aerospace applications. The detailed 2025 consumption data were withheld to protect company data.
- where: Lunar oxygen (concept)
line: Wikipedia describes lunar ilmenite as a target for oxygen extraction by reduction with CO and H2 buffers, and gives no yield. The arXiv paper 2601.14719 gives an apparent yield of 1.10 wt% oxygen under hydrogen reduction, with its temperature not stated in the text read.
can_do:
- label: Density
benchmark: density
line: Calculated density is 4.79 gm/cc (webmineral). Wikipedia gives a specific gravity of 4.7 to 4.79 in the infobox.
- label: Melting
benchmark: melting_point
value: 1710 °C
line: Wikipedia gives the liquidus of ilmenite as 1710 °C at a peritectic point.
- label: Hardness
benchmark: mohs_hardness
value: 5 to 6 Mohs
line: Wikipedia gives Mohs hardness 5 to 6 in the infobox and 5.6 to 6 in the text. Webmineral gives 5 to 5.5 on an apatite-knife scale.
- label: Oxygen
benchmark: hydrogen_reduction_oxygen_yield
line: The arXiv paper 2601.14719 gives an apparent 1.10 wt% oxygen for ilmenite under hydrogen reduction. Prior work it cites reports up to 1-2 wt% oxygen via hydrogen reduction at 900 °C for ilmenite-rich regolith.
compare: Ilmenite is a dense, high-melting oxide with a mid-range hardness, and it is the largest source of titanium concentrate. The USGS names rutile, slag and synthetic rutile as alternative feedstocks. We did not read density or melting data for those in this run, so this profile makes no numeric comparison with them.
compare_rows:
- label: Density
benchmark: density
- label: Melting point
benchmark: melting_point
- label: Mohs hardness
benchmark: mohs_hardness
handling:
- No handling or hazard data for ilmenite were found in the sources read. Check the supplier's safety data sheet before handling the powder.
- Wikipedia names CO and H2 as the buffers for the lunar reduction concept. Their hazards are not covered by this record.
good_for:
- Titanium feedstock. Wikipedia says more than 80 percent of titanium concentrate comes from ilmenite.
- Lunar oxygen research. Wikipedia describes ilmenite as a target for oxygen extraction, and one arXiv paper gives an apparent yield of 1.10 wt% oxygen.
watch_out:
- 'The Mohs hardness differs between sources: 5 to 6 in the infobox, and 5 to 5.5 on an apatite-knife scale on webmineral.'
- The USGS production figures are titanium dioxide content, not the mass of ilmenite mineral.
- The 1.10 wt% oxygen yield is apparent, comes from one paper, and its temperature is not stated in the text read. The lunar highland and south-pole simulants give far lower yields, 0.02 wt% and 0.01 wt%.
verdict: Ilmenite is a dense iron-titanium oxide with a high liquidus temperature (1710 °C) and a well-documented titanium supply chain. For oxygen extraction, one arXiv paper gives an apparent yield of 1.10 wt% oxygen, while its lunar simulant results are much lower. Energy and temperature data for a working plant are still missing.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Ilmenite | web | 2026 | 10 values | |
| Ilmenite mineral data | database | 2026 | 4 values | |
| Mineral Commodity Summaries 2026, Titanium Mineral Concentrates (pages 199 and 200 of the compilation) | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026, Titanium and Titanium Dioxide | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026, Final 2025 List of Critical Minerals (table in the introduction) | report | 2025 | 0 values | |
| Teichert Aggregates, Ilmenite Safety Data Sheet (effective 06/01/24, replaces June 2018) | datasheet | 2024 | 3 values | |
| Valentine Clays, Safety Data Sheet: Ilmenite (EU format, Regulation (EC) No 2020/878) | datasheet | 2 values | ||
| Pottery Crafts, Ilmenite MSDS (product P3324) | datasheet | 2025 | 1 value | |
| Physicochemical properties of lunar regolith simulant for in situ oxygen production | paper | 2026 | 4 values | |
| Handbook of Mineralogy, Ilmenite (Mineral Data Publishing) | handbook | 2005 | 2 values |
Updated