Manganese Mn

spore: profile
id: manganese
spore_version: 0.2
family: manganese
name: Manganese
abbreviation: Mn
role: alloying and deoxidising metal for steel, and the manganese element in dry cell and lithium-ion battery materials
category: metals
type: heavy-metals
summary: |
  Manganese (Mn, atomic number 25) is a brittle transition metal with a density of 7.21 g/cm3 for alpha-manganese at 20 °C and a melting point of 1246 °C (Goodfellow). Its main use is in steel: Goodfellow lists its steelmaking roles as deoxidiser, desulphuriser and austenite stabiliser, and the USGS says consumption closely follows the steel industry. The United States imported 100 % of its apparent manganese consumption in every year from 2021 to 2025e (USGS 2026).
best_for: 'Steelmaking: manganese deoxidises and desulphurises steel and stabilises austenite (Goodfellow), and the USGS reports no satisfactory substitute in its major applications'
weakest_at: 'Brittleness and supply: alpha-manganese is completely brittle at room temperature with no measurable elongation (Goodfellow), and the United States imports all of its supply (USGS 2026)'
identity:
  formula: Mn (element, atomic number 25); alpha-manganese at room temperature is a cubic structure with 58 atoms per cell (Goodfellow)
  crystal_system: cubic
  source: goodfellow-mn
  where: General Properties table, Atomic Number row (25); Crystal Structure row (alpha-Mn BCC-derived cubic, 58 atoms per cell)
  designations: []
tags:
  environments: []
  stresses: []
  applications:
    - structures
    - batteries
properties:
  - benchmark: density
    label: Density, alpha-manganese at 20 °C
    value: 7.21
    unit: g/cm3
    scope: material
    conditions:
      temperature: 20 °C
      form: alpha-manganese, the room-temperature allotrope
    method: Value printed in the Goodfellow manganese material page, General Properties table
    status: ground
    source: goodfellow-mn
    where: General Properties table, row Density (20 °C, alpha-Mn)
  - benchmark: density
    label: Density of solid manganese
    value: 7.47
    unit: g/cm3
    scope: material
    conditions:
      temperature: not stated in the row
      unit_in_source: 7470 kg m-3
    method: Value printed in the WebElements manganese physics page as 7470 kg m-3, converted to g/cm3 (7.47 g/cm3)
    status: ground
    note: Goodfellow prints 7.21 g/cm3 at 20 °C for alpha-manganese. The two densities differ by 0.26 g/cm3 and both are kept with their conditions.
    source: webelements-mn
    where: Density of solid row
  - benchmark: melting_point
    label: Melting point, manganese
    value: 1246
    unit: °C
    scope: material
    conditions:
      basis: element, no condition printed in the row
    method: Value printed in the Goodfellow manganese material page, General Properties table
    status: ground
    source: goodfellow-mn
    where: General Properties table, row Melting Point 1,246 °C (1,519 K)
  - benchmark: boiling_point
    label: Boiling point, manganese
    value: 2061
    unit: °C
    scope: material
    conditions:
      basis: element, no condition printed in the row
    method: Value printed in the Goodfellow manganese material page, General Properties table
    status: ground
    source: goodfellow-mn
    where: General Properties table, row Boiling Point 2,061 °C (2,334 K)
  - benchmark: thermal_conductivity
    label: Thermal conductivity, manganese (Goodfellow)
    value: 7.8
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: not stated in the row
      unit_in_source: W/m·K
    method: Value printed in the Goodfellow manganese material page, General Properties table
    status: ground
    source: goodfellow-mn
    where: General Properties table, row Thermal Conductivity 7.8 W/m·K, no temperature given
  - benchmark: thermal_conductivity
    label: Thermal conductivity, manganese (WebElements)
    value: 7.8
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: not stated in the row
      unit_in_source: W m-1 K-1
    method: Value printed in the WebElements manganese physics page, Thermal conductivity row
    status: ground
    source: webelements-mn
    where: Thermal conductivity row, value 7.8 W m-1 K-1
  - benchmark: cte
    label: Coefficient of linear thermal expansion, manganese
    value: 21.7
    unit: ppm/K
    scope: material
    conditions:
      temperature: not stated in the row
      unit_in_source: 10-6 K-1
    method: Value printed in the WebElements manganese physics page, Coefficient of linear thermal expansion row
    status: ground
    source: webelements-mn
    where: Coefficient of linear thermal expansion row, value 21.7 × 10-6 K-1
  - benchmark: elastic_modulus
    label: Young's modulus, manganese (Goodfellow)
    value: 198
    unit: GPa
    scope: material
    conditions:
      temperature: not stated in the row
    method: Value printed in the Goodfellow manganese material page, Mechanical Properties table
    status: ground
    source: goodfellow-mn
    where: Mechanical Properties table, row Elastic (Young's) Modulus 198 GPa, no temperature given
  - benchmark: elastic_modulus
    label: Young's modulus, manganese (WebElements)
    value: 198
    unit: GPa
    scope: material
    conditions:
      temperature: not stated in the row
    method: Value printed in the WebElements manganese physics page, Young's modulus row
    status: ground
    source: webelements-mn
    where: Young's modulus row, value 198 GPa
  - benchmark: electrical_resistivity
    label: Electrical resistivity, manganese
    value: 144
    unit: 10-8 Ω·m
    scope: material
    conditions:
      temperature: not stated in the row
      unit_in_source: 144 × 10-8 Ω m
    method: Value printed in the WebElements manganese physics page, Electrical resistivity row, as 144 × 10-8 Ω m; the site registry converts it to Ω·m
    status: ground
    source: webelements-mn
    where: Electrical resistivity row, value 144 × 10-8 Ω m
  - benchmark: mohs_hardness
    label: Mohs hardness, manganese
    value: 6
    unit: '-'
    scope: material
    conditions:
      basis: mineral hardness scale, no temperature printed
    method: Value printed in the WebElements manganese physics page, Mineral hardness row (no units)
    status: ground
    note: Custom benchmark name, not in the property canon. Goodfellow prints Mohs ~6 for alpha-Mn.
    source: webelements-mn
    where: Mineral hardness row, value 6.0 (no units)
corrosion:
  - environment: Moist air at room temperature
    headline: Manganese oxidises slowly in moist air.
    effect: Goodfellow says it oxidises slowly and forms a mixed MnO, Mn2O3 and Mn3O4 scale.
    rating: low
    conditions:
      basis: moist air at room temperature, as printed; no exposure duration printed
    source: goodfellow-mn
    where: Chemical Properties table, row Corrosion in Air
risks:
  hazards:
    - text: The ECHA C&L aggregate on PubChem for manganese (EC 231-105-1) gives the signal word Danger and the hazard statements H228 (flammable solid), H319 (causes serious eye irritation), H411 (toxic to aquatic life with long lasting effects) and H412 (harmful to aquatic life with long lasting effects).
      ghs:
        - H228
        - H319
        - H411
        - H412
      source: pubchem-mn
      where: GHS Classification section, aggregated information from 22 ECHA notifications covering 3,101 company reports
    - text: Of the 3,101 company reports in the same aggregate, 1,429 (46.1 %) state that the substance does not meet GHS hazard criteria.
      ghs: []
      source: pubchem-mn
      where: GHS Classification section, notifications and non-classification statement
    - text: 'Other classifications differ: NITE-CMC (FY2022) uses the signal word Danger with a GHS08 pictogram and lists H360, H372, H401 and H411, and Safe Work Australia lists only H372.'
      ghs: []
      source: pubchem-mn
      where: GHS Classification section, other sources paragraph
    - text: NIOSH prints a TWA of 0.1 mg/m3 with a skin notation for manganese, and an OSHA PEL of C 5 mg/m3.
      ghs: []
      source: niosh-npg-mn
      where: Exposure limits, REL and OSHA PEL entries
  failure_risks:
    - mode: Brittle fracture at room temperature
      trigger: Loading of the unalloyed metal at room temperature
      consequence: Goodfellow says the metal is completely brittle at room temperature with no measurable elongation, so the unalloyed metal is not a structural material on its own.
      severity: high
      source: goodfellow-mn
      where: Mechanical Properties table, row Brittleness
    - mode: Oxide scale in moist air
      trigger: Moist air at room temperature
      consequence: Slow oxidation to a mixed MnO, Mn2O3 and Mn3O4 scale (Goodfellow).
      severity: low
      source: goodfellow-mn
      where: Chemical Properties table, row Corrosion in Air
  side_effects: []
  handling:
    - text: The ECHA aggregate on PubChem lists the precautionary codes P210 (keep away from heat), P273 (avoid release to the environment) and P280 (wear protective equipment).
      source: pubchem-mn
    - text: Keep airborne manganese within the NIOSH TWA of 0.1 mg/m3 with skin notation, and within the OSHA ceiling of C 5 mg/m3.
      source: niosh-npg-mn
  mitigations: []
uses:
  - application: structures
    device: Steel deoxidiser, desulphuriser and austenite stabiliser
    example: Goodfellow lists the steelmaking roles of manganese as deoxidiser (MnO), desulphuriser (MnS) and austenite stabiliser. The USGS says consumption closely follows the steel industry.
    source: goodfellow-mn
    where: Chemical Properties table, row Role in Steelmaking Chemistry
  - application: batteries
    device: Manganese dioxide in dry cell batteries
    example: The USGS says some manganese ore is consumed for nonmetallurgical uses, including dry cell batteries.
    source: usgs-mcs2026-manganese
    where: Domestic Production and Use paragraph
  - application: batteries
    device: Spinel LiMn2O4 cathode in lithium-ion batteries
    example: Huang et al. review spinel LiMn2O4 as a lithium-ion cathode and note that it degrades badly at extreme voltages and during high-temperature operation.
    source: huang-spinel-review
    where: Abstract
supply:
  - subject: Manganese (world mine production, 2025e, manganese content)
    abundance: 'USGS 2026: world reserves are 1,800,000 thousand metric tons, and South Africa accounts for an estimated 70 % of world manganese resources. Land-based resources are large but irregularly distributed.'
    producers:
      - country: South Africa (mine production 2025e, 7,600 thousand t of 20,000 thousand t world total)
        year: 2025
      - country: Gabon (mine production 2025e, 5,000 thousand t)
        year: 2025
      - country: Ghana (mine production 2025e, 2,000 thousand t)
        year: 2025
      - country: Australia (mine production 2025e, 1,600 thousand t)
        year: 2025
    critical_lists: []
    recycling: 'USGS: manganese is recycled incidentally in ferrous and nonferrous scrap, scrap recovery specifically for manganese is negligible, and manganese is recovered along with iron from steel slag.'
    substitutes:
      - 'USGS: manganese has no satisfactory substitute in its major applications.'
    source: usgs-mcs2026-manganese
    where: Events, Trends, and Issues; World Mine Production and Reserves table (2025e); World Resources paragraph; Recycling; Substitutes
  - subject: Manganese (United States import dependence and sources)
    abundance: 'USGS 2026: net import reliance was 100 % of apparent consumption in each year from 2021 to 2025e.'
    producers:
      - country: Gabon (manganese ore imports, 2021 to 2024)
        share_percent: 64
        year: 2024
      - country: South Africa (manganese ore imports, 2021 to 2024)
        share_percent: 24
        year: 2024
      - country: Malaysia (ferromanganese imports, 2021 to 2024)
        share_percent: 26
        year: 2024
    critical_lists: []
    source: usgs-mcs2026-manganese
    where: Salient Statistics table (net import reliance); Import Sources (2021 to 2024)
documents:
  - title: 'USGS Mineral Commodity Summaries 2026: Manganese'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf
    year: 2026
  - title: Goodfellow, Manganese material data page
    type: datasheet
    url: https://www.goodfellow.com/usa/material/metals/manganese
  - title: WebElements, Manganese physical properties
    type: database
    url: https://www.webelements.com/manganese/physics.html
  - title: PubChem compound record for manganese (CID 23930), GHS classification
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23930/JSON?heading=GHS+Classification
  - title: NIST Atomic Weights and Isotopic Compositions for All Elements, manganese
    type: database
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Mn&all=all&ascii=html
  - title: NIOSH Pocket Guide to Chemical Hazards, manganese entry
    type: report
    url: https://www.cdc.gov/niosh/npg/npgd0380.html
  - title: Lithium Manganese Spinel Cathodes for Lithium-Ion Batteries, Advanced Energy Materials (DOI 10.1002/AENM.202000997)
    type: paper
    url: https://dspace.mit.edu/handle/1721.1/133242
  - title: US Patent 5,932,086, Process for making manganese
    type: report
    url: https://patents.google.com/patent/US5932086
gaps:
  - 'Specific heat: not printed by Goodfellow or WebElements, so not entered.'
  - 'Electrical resistivity from Goodfellow: 1,440 nΩ·m at 20 °C for alpha-Mn. The nΩ·m unit is not in the site unit registry, so only the WebElements value is entered.'
  - 'Hardness: Goodfellow prints about 196 HV (Vickers) and WebElements prints a Brinell value of 196 MN m-2. No canonical hardness property exists, so neither is entered. Mohs 6 is entered as a custom benchmark.'
  - 'Poisson''s ratio: WebElements prints no data, and Goodfellow does not print one.'
  - 'Space group: Goodfellow prints Im-3m in the crystal structure row and I-43m in its density note, so space_group is left out. Lattice parameter: not printed in a source read in this run.'
  - 'CAS number: not printed by any source read in this run, so identity has no cas.'
  - 'Designations: no UNS, EN, ASTM or other designation for unalloyed manganese was printed in a source read in this run, so designations is empty.'
  - 'Critical-mineral list status: the USGS 2026 manganese summary read in this run prints no critical-mineral list, and the EU list was not opened, so critical_lists is empty.'
  - 'Crustal abundance: Wikipedia was read but is used for composition and history only, so no abundance value is entered.'
  - 'Production process beyond electrolysis: the patent describes leaching manganese oxide with sulphuric acid and plating the metal onto a cathode. No other primary source on the process was read.'
  - 'Corrosion in acids, seawater and at elevated temperature: no source was read that prints a rate or a rating.'
  - 'Space-environment tests (outgassing, atomic oxygen, radiation): none found in the sources read.'
  - 'Lithium-ion cathode numbers: the full Huang et al. text could not be downloaded in this run (HTTP 429), so only the abstract statement is used and no capacity or voltage values are entered.'
  - 'Atomic weight: not a property-canon benchmark; the NIST value 54.938044 is used in recipe parts only.'
  - 'Media: no public-domain image of manganese metal was checked in this run, so media is empty.'
sources:
  usgs-mcs2026-manganese:
    title: Mineral Commodity Summaries 2026, Manganese, February 2026
    id: USGS MCS 2026, prepared by Ji-Eun Kim
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  goodfellow-mn:
    title: Goodfellow, Manganese material page (general, mechanical and chemical properties)
    id: Goodfellow material page, metals, manganese
    url: https://www.goodfellow.com/usa/material/metals/manganese
    kind: datasheet
    license: supplier web page (cited, not reproduced)
  webelements-mn:
    title: 'WebElements, Manganese: physical properties'
    id: WebElements manganese, physics page
    url: https://www.webelements.com/manganese/physics.html
    kind: database
    license: WebElements (cited, not reproduced)
  pubchem-mn:
    title: 'PubChem compound record: Manganese (CID 23930), GHS Classification section'
    id: CID 23930, EC 231-105-1, ECHA C&L Inventory aggregated notifications
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23930/JSON?heading=GHS+Classification
    kind: database
    license: PubChem (NCBI), public domain; sections attributed to ECHA
  nist-atomic-weights-mn:
    title: NIST Atomic Weights and Isotopic Compositions for All Elements, manganese
    id: NIST standard atomic weight 54.938044(3)
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Mn&all=all&ascii=html
    kind: database
    license: US government data
  niosh-npg-mn:
    title: NIOSH Pocket Guide to Chemical Hazards, manganese entry
    id: NIOSH NPG, npgd0380
    url: https://www.cdc.gov/niosh/npg/npgd0380.html
    kind: handbook
    license: US government data
  huang-spinel-review:
    title: Lithium Manganese Spinel Cathodes for Lithium-Ion Batteries, Advanced Energy Materials
    id: DOI 10.1002/AENM.202000997
    url: https://dspace.mit.edu/handle/1721.1/133242
    kind: paper
    license: CC BY-NC-SA 4.0 (MIT DSpace accepted manuscript)
  us5932086:
    title: US Patent 5,932,086, Process for making manganese
    id: US 5,932,086
    url: https://patents.google.com/patent/US5932086
    kind: web
    license: patent publication (cited, not reproduced)
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 11
  unreachable: 1
  caveats: 6
  note: Values were read by an AI assistant on 2026-10-26 from the pages and PDFs named in each entry. The USGS summary was read from text extracted from the PDF. Web pages were read through a fetch tool that returns a summary, so every value still needs the verify-values check. The full Huang et al. text could not be downloaded (HTTP 429), so no battery numbers are entered. Density differs between Goodfellow (7.21 g/cm3 at 20 °C) and WebElements (7.47 g/cm3); both are kept with their conditions.
story:
  recipe:
    line: Manganese is a single-element metal (Mn, atomic number 25). Electrolytic manganese metal is made by leaching manganese oxide with sulphuric acid, purifying the solution, and plating the metal onto a cathode in flake form (US patent 5,932,086).
    parts:
      - name: Manganese
        symbol: Mn
        atoms: 1
        atomic_weight: 54.938044
        role: The base metal. Density 7.21 g/cm3 at 20 °C for alpha-manganese (Goodfellow), and completely brittle at room temperature.
  risk_groups:
    - title: For people
      lead: The ECHA aggregate lists the metal as a flammable solid with serious eye irritation, and the airborne exposure limit is low.
      level: 2
      verdict: Low airborne limit and eye hazard; control dust.
      points:
        - label: Manganese dust
          line: NIOSH prints a TWA of 0.1 mg/m3 with a skin notation, and the OSHA PEL is a ceiling of C 5 mg/m3.
        - label: Metal classification
          line: The ECHA aggregate on PubChem lists H228, H319, H411 and H412 with signal word Danger, and 46.1 % of company reports say the substance does not meet the criteria.
    - title: If it fails
      lead: The main failure routes are brittle fracture of the metal at room temperature, and slow oxidation in moist air.
      points:
        - label: Brittle at room temperature
          line: Goodfellow says alpha-manganese is completely brittle at room temperature, with no measurable elongation.
        - label: Moist air
          line: Goodfellow says it oxidises slowly in moist air and forms a mixed MnO, Mn2O3 and Mn3O4 scale.
  why: Manganese is mainly a steel input. Goodfellow lists its steelmaking roles as deoxidiser, desulphuriser and austenite stabiliser, and the USGS says consumption closely follows the steel industry and that no satisfactory substitute exists in its major applications. The metal is brittle at room temperature, so its value lies in alloys and battery materials rather than as a structural metal on its own.
  uses:
    - where: Steel
      line: Goodfellow lists manganese as a deoxidiser (MnO), desulphuriser (MnS) and austenite stabiliser in steelmaking. The USGS says consumption closely follows the steel industry.
    - where: Dry cell batteries
      line: The USGS says some manganese ore is consumed for nonmetallurgical uses, including dry cell batteries.
    - where: Lithium-ion cathodes
      line: Huang et al. review spinel LiMn2O4 as a lithium-ion cathode and note that it degrades badly at extreme voltages and during high-temperature operation.
  can_do:
    - label: Weight
      value: 7.21 g/cm3
      benchmark: density
      line: Goodfellow prints a density of 7.21 g/cm3 for alpha-manganese at 20 °C. WebElements prints 7470 kg m-3, which is 7.47 g/cm3.
    - label: Melting
      value: 1246 °C
      benchmark: melting_point
      line: Goodfellow prints a melting point of 1246 °C for manganese.
    - label: Heat
      value: 7.8 W/(m·K)
      benchmark: thermal_conductivity
      line: Goodfellow and WebElements both print a thermal conductivity of 7.8 W/(m·K), with no temperature given.
    - label: Stiffness
      value: 198 GPa
      benchmark: elastic_modulus
      line: Goodfellow and WebElements both print a Young modulus of 198 GPa, with no temperature given.
  compare: Manganese at 20 °C has a density of 7.21 g/cm3 in Goodfellow and 7.47 g/cm3 in WebElements, and a melting point of 1246 °C. Its thermal conductivity of 7.8 W/(m·K) is the same in both sources, with no temperature printed. The two density values differ by 0.26 g/cm3, and both are kept with their conditions.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Melting point
      benchmark: melting_point
    - label: Thermal conductivity
      benchmark: thermal_conductivity
  handling:
    - Keep the metal away from heat, avoid release to the environment and wear protective equipment (P210, P273 and P280, ECHA aggregate on PubChem).
    - Keep airborne manganese within the NIOSH TWA of 0.1 mg/m3 with skin notation.
    - Treat the metal as toxic to aquatic life, with H411 and H412 in the ECHA aggregate on PubChem.
  good_for:
    - 'Steel: manganese deoxidises and desulphurises steel and stabilises its austenite (Goodfellow).'
    - 'Batteries: manganese dioxide is used in dry cells, and spinel LiMn2O4 is studied as a lithium-ion cathode (USGS; Huang et al.).'
    - 'Supply: South Africa mined an estimated 7,600 thousand t of 20,000 thousand t world output in 2025e (USGS 2026).'
  watch_out:
    - 'Brittleness: alpha-manganese is completely brittle at room temperature with no measurable elongation (Goodfellow).'
    - 'Hazard classification: the ECHA aggregate lists H228, H319, H411 and H412, but 46.1 % of company reports say the substance does not meet GHS criteria (PubChem).'
    - 'Import dependence: the United States imported 100 % of its apparent manganese consumption from 2021 to 2025e (USGS 2026).'
    - No space outgassing, erosion or radiation data for manganese were found in the sources read.
  verdict: Manganese is mainly an alloying metal. Goodfellow gives a density of 7.21 g/cm3 and a melting point of 1246 °C, and the metal is brittle at room temperature, so it is used in steel and battery materials rather than as a structural metal. The main hazard data are an ECHA aggregate and a low airborne exposure limit, and this profile has no space-environment test data.
media: []