spore: profile
id: antimony
spore_version: 0.2
family: low-melting-metals-and-solders
name: Antimony
abbreviation: Sb
role: alloying metal for lead battery grids and bearing alloys, and semiconductor dopant
category: metals
type: heavy-metals
summary: |
  Antimony is the element Sb (atomic number 51), a silvery, lustrous, hard and brittle metalloid. Metal products, including flame retardants, took 49 % of U.S. antimony use in 2025, and antimonial lead for battery grids and ammunition took 40 % (USGS). High-purity antimony is used in semiconductor devices. The 99.5 % pellet grade from Goodfellow has a density of 6.68 g/cm3 at 20 °C, a melting point of 630.7 °C and a thermal conductivity of 24.4 W/(m·K) at 0 to 100 °C.
best_for: Hardening lead for battery grids and bearing alloys, and flame-retardant antimony oxides
weakest_at: 'Brittleness and toxicity: Mohs hardness 3 to 3.3, and dust and stibine gas that are hazardous to people'
identity:
  formula: Sb (element, atomic number 51); 99.5 % pellet grade (Goodfellow)
  cas: 7440-36-0
  crystal_system: rhombohedral
  source: goodfellow-sb
  where: Crystal structure row of the 99.5 % antimony pellets table (prints Rhombohedral); CAS Number line on the same page
tags:
  applications:
    - electronics-and-chips
    - batteries
    - mechanisms
properties:
  - benchmark: density
    label: Density of 99.5 % antimony pellets (Goodfellow)
    value: 6.68
    unit: g/cm3
    scope: material
    conditions:
      form: polycrystalline pellets, 99.5 % purity
      temperature: 20 °C
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Density row (6.68@20)
  - benchmark: density
    label: Density of antimony (PubChem)
    value: 6.68
    unit: g/cm3
    scope: material
    conditions:
      temperature: 25 °C
    method: Value listed in the density section of the PubChem record
    status: ground
    source: pubchem-sb
    where: Experimental Properties, Density section, entry 6.68 @25 °C
  - benchmark: density
    label: Density of solid antimony (WebElements)
    value: 6697
    unit: kg/m3
    scope: material
    conditions:
      temperature: not stated on the page
    method: Value printed on a reference-database physical properties page
    status: ground
    source: webelements-sb
    where: Density properties, Density of solid row (6697 kg m-3)
  - benchmark: melting_point
    label: Melting point of 99.5 % antimony pellets (Goodfellow)
    value: 630.7
    unit: °C
    scope: material
    conditions:
      form: polycrystalline pellets, 99.5 % purity
      pressure: not stated
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Melting point row (630.7)
  - benchmark: melting_point
    label: Melting point of antimony (PubChem)
    value: 630.628
    unit: °C
    scope: material
    conditions:
      form: elemental antimony
      pressure: not stated
    method: Value listed in the melting point section of the PubChem record
    status: ground
    note: Other entries in the same record read 630 °C and 630.028 °C (gray antimony).
    source: pubchem-sb
    where: Experimental Properties, Melting Point section, entry 630.628 °C
  - benchmark: boiling_point
    label: Boiling point of 99.5 % antimony pellets (Goodfellow)
    value: 1750
    unit: °C
    scope: material
    conditions:
      pressure: not stated
    method: Value printed on the supplier product page
    status: ground
    note: Other sources read differently; PubChem gives 1587 °C at 760 mmHg and the ICSC card gives 1635 °C.
    source: goodfellow-sb
    where: Properties table on the product page, Boiling point row (1750)
  - benchmark: boiling_point
    label: Boiling point of antimony (PubChem)
    value: 1587
    unit: °C
    scope: material
    conditions:
      pressure: 760 mmHg
    method: Value listed in the boiling point section of the PubChem record
    status: ground
    note: The same record also prints 1635 °C and 2975 °F.
    source: pubchem-sb
    where: Experimental Properties, Boiling Point section, entry 1587 °C @760 [mm Hg]
  - benchmark: electrical_resistivity
    label: Electrical resistivity of 99.5 % antimony pellets (Goodfellow)
    value: 40.1
    unit: µΩ·cm
    scope: material
    conditions:
      temperature: 20 °C
      form: polycrystalline pellets, 99.5 % purity
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Electrical properties row, Electrical resistivity (40.1@20°C)
  - benchmark: electrical_resistivity
    label: Electrical resistivity of antimony (WebElements)
    value: 40
    unit: µΩ·cm
    scope: material
    conditions:
      unit_in_source: 40 × 10-8 Ω m
      temperature: not stated on the page
    method: Printed as 40 × 10-8 Ω m and converted by Space Mushroom to µΩ·cm (1 Ω·m = 10^8 µΩ·cm, so 40 × 10-8 Ω m = 40 µΩ·cm). The page also writes the unit as mΩ cm, which reads as a typo for µΩ cm.
    status: ground
    source: webelements-sb
    where: Electrical properties, Electrical resistivity row
  - benchmark: thermal_conductivity
    label: Thermal conductivity of 99.5 % antimony pellets (Goodfellow)
    value: 24.4
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 0 to 100 °C
      form: polycrystalline pellets, 99.5 % purity
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Thermal conductivity row (24.4@0-100°C)
  - benchmark: thermal_conductivity
    label: Thermal conductivity of antimony (WebElements)
    value: 24
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: not stated on the page
    method: Value printed on a reference-database physical properties page
    status: ground
    source: webelements-sb
    where: Heat and conduction, Thermal conductivity row (24 W m-1 K-1)
  - benchmark: specific_heat
    label: Specific heat capacity of 99.5 % antimony pellets (Goodfellow)
    value: 205
    unit: J/(kg·K)
    scope: material
    conditions:
      temperature: 25 °C
      form: polycrystalline pellets, 99.5 % purity
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Specific heat row (205@25°C)
  - benchmark: cte
    label: Coefficient of thermal expansion of 99.5 % antimony pellets (Goodfellow)
    value: 9
    unit: ppm/K
    scope: material
    conditions:
      unit_in_source: x10-6 K-1
      temperature: 0 to 100 °C
      form: polycrystalline pellets, 99.5 % purity
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Coefficient of thermal expansion row (9@0-100°C)
  - benchmark: cte
    label: Coefficient of linear thermal expansion (WebElements)
    value: 11
    unit: ppm/K
    scope: material
    conditions:
      unit_in_source: 10-6 K-1
      temperature: not stated on the page
    method: Value printed on a reference-database physical properties page
    status: ground
    source: webelements-sb
    where: Heat and conduction, Coefficient of linear thermal expansion row (11 × 10-6 K-1)
  - benchmark: elastic_modulus
    label: Tensile modulus of 99.5 % antimony pellets (Goodfellow)
    value: 54.7
    unit: GPa
    scope: material
    conditions:
      material_condition: Polycrystalline
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Tensile modulus row (54.7)
  - benchmark: elastic_modulus
    label: Young's modulus of antimony (WebElements)
    value: 55
    unit: GPa
    scope: material
    conditions:
      temperature: not stated on the page
    method: Value printed on a reference-database physical properties page
    status: ground
    source: webelements-sb
    where: Elastic properties, Young's modulus row (55 GPa)
  - benchmark: shear_modulus
    label: Rigidity (shear) modulus of antimony (WebElements)
    value: 20
    unit: GPa
    scope: material
    conditions:
      temperature: not stated on the page
    method: Value printed on a reference-database physical properties page
    status: ground
    source: webelements-sb
    where: Elastic properties, Rigidity modulus row (20 GPa)
  - benchmark: bulk_modulus
    label: Bulk modulus of 99.5 % antimony pellets (Goodfellow)
    value: 42
    unit: GPa
    scope: material
    conditions:
      material_condition: Polycrystalline
    method: Value printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Bulk modulus row (42)
  - benchmark: poissons_ratio
    label: Poisson's ratio of 99.5 % antimony pellets (Goodfellow)
    value: 0.25
    value_high: 0.33
    bound: range
    unit: '-'
    scope: material
    conditions:
      material_condition: Polycrystalline
    method: Range printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Poisson's ratio row (0.25-0.33)
  - benchmark: mohs_hardness
    label: Hardness, Mohs scale (Goodfellow)
    value: 3
    value_high: 3.3
    bound: range
    unit: '-'
    scope: material
    conditions:
      material_condition: Polycrystalline
    method: Range printed on the supplier product page
    status: ground
    source: goodfellow-sb
    where: Properties table on the product page, Hardness - Mohs row (3-3.3)
corrosion:
  - environment: Dry air and moist air at room temperature
    headline: Antimony does not tarnish in dry air, but it tarnishes slowly in moist air.
    effect: PubChem's stability entry reads not tarnished in dry air but slowly in moist air, and a second entry says it is slightly oxidized in air. The record gives no rate, time or humidity level.
    rating: low
    conditions:
      basis: qualitative statements in the PubChem record, not a rate test
    source: pubchem-sb
    where: Experimental Properties, Stability/Shelf Life section (two entries)
  - environment: Hot concentrated sulfuric acid
    headline: Hot concentrated sulfuric acid attacks antimony, while cold dilute acids do not.
    effect: PubChem records that antimony is not affected by cold dilute acids and is attacked by hot concentrated sulfuric acid. It also says antimony is insoluble in dilute acid and soluble in hot concentrated H2SO4.
    rating: moderate
    conditions:
      basis: qualitative statement in the PubChem record; no concentration or temperature given
    source: pubchem-sb
    where: Experimental Properties, Other Experimental Properties and Solubility sections
  - environment: Aqua regia and hot concentrated hydrochloric acid
    headline: Aqua regia attacks antimony readily, and finely divided antimony reacts with hot concentrated hydrochloric acid.
    effect: PubChem records that antimony is readily attacked by aqua regia and that finely divided antimony reacts with hot concentrated hydrochloric acid. The reaction with acid can give stibine gas, which is toxic.
    rating: moderate
    conditions:
      basis: qualitative statements in the PubChem record; no rates given
    source: pubchem-sb
    where: Experimental Properties, Other Experimental Properties section
risks:
  hazards:
    - text: 'PubChem''s ECHA C&L aggregate for 748 company reports: 18.7 % (140 of 748) say the substance does not meet GHS criteria. Hazard codes given in the reports include H301 (18.2 %, toxic if swallowed), H302 (23.4 %, harmful if swallowed), H332 (26.9 %, harmful if inhaled), H351 (31.8 %, suspected of causing cancer) and H373 (20.5 %, organ damage with repeated exposure). Signal word Danger. The record does not say which antimony form each report covers.'
      ghs:
        - H301
        - H302
        - H332
        - H351
        - H373
      source: pubchem-sb
      where: Hazards Identification, GHS Classification, first block (748 reports)
    - text: 'ICSC 0775 for metallic antimony: the TLV is 0.5 mg/m3 as an 8-hour time-weighted average. Repeated or prolonged contact with dust or fumes may cause dermatitis and may affect the lungs, which may result in pneumoconiosis. The card applies only to metallic antimony.'
      ghs: []
      source: icsc-sb
      where: Occupational exposure limits and Effects of long-term or repeated exposure sections
    - text: UN2871, antimony powder, shipped under DOT Division 6.1 (poisonous materials), packing group III (PubChem); ICSC 0775 gives the same UN number and class.
      ghs: []
      source: pubchem-sb
      where: Hazards Identification, DOT Hazard Classification
  failure_risks:
    - mode: Dust explosion
      trigger: Antimony in powder or granular form dispersed in air, or finely divided particles
      consequence: PubChem and ICSC both record that finely dispersed particles form explosive mixtures in air. ICSC adds that a dust explosion is possible and that the powder is combustible under specific conditions.
      severity: moderate
      source: icsc-sb
      where: Fire and explosion section; PubChem Fire Hazards section
    - mode: Stibine (SbH3) gas formation
      trigger: Contact with acids, or heating of antimony in the presence of acid
      consequence: PubChem reports that heating or contact with acid releases toxic fumes of SbH3, and ICSC warns that contact with acids may generate the toxic gas stibine.
      severity: moderate
      source: pubchem-sb
      where: Experimental Properties, Decomposition section; ICSC 0775 fire and explosion section
  side_effects:
    - text: On combustion antimony gives toxic fumes of antimony oxides, and in a fire it gives off irritating or toxic fumes.
      affects: People in the area of a fire, and the fire response
      source: icsc-sb
      where: Fire and explosion section
    - text: Stibine (SbH3) can be released on contact with acid. It is a toxic gas, and the record does not give a release rate.
      affects: Air around the metal where it contacts acid
      source: pubchem-sb
      where: Experimental Properties, Decomposition section
  handling:
    - text: Prevent dispersion of dust. Keep the metal away from oxidizing agents, halogens and acids.
      source: icsc-sb
      where: Prevention section (fire and spillage)
    - text: Use a particulate filter respirator adapted to the airborne concentration, and sweep spills into covered containers, moistened first to prevent dusting.
      source: icsc-sb
      where: Personal protection and spillage disposal sections
    - text: The ICSC card gives a TLV of 0.5 mg/m3 as an 8-hour TWA. Check the current national limit before use, because the card dates from 2006.
      source: icsc-sb
      where: Occupational exposure limits section
  mitigations:
    - text: Closed system, dust explosion-proof electrical equipment and lighting, and no open flames near the powder.
      source: icsc-sb
      where: Prevention section (fire and explosion)
uses:
  - application: batteries
    device: Antimonial lead grids for lead-acid storage batteries
    example: 'USGS: secondary antimony is recovered as antimonial lead from spent lead-acid batteries and is intended for the lead-acid battery industry. Antimonial lead and ammunition took 40 % of U.S. use in 2025.'
    source: usgs-mcs2026-antimony
    where: Domestic Production and Use paragraph
  - application: electronics-and-chips
    device: High-purity antimony for semiconductor devices
    example: 'PubChem: high-purity antimony (up to 99.9 %) has a limited but important application in the manufacture of semiconductor devices.'
    source: pubchem-sb
    where: Uses section, entry on high-purity antimony
  - application: mechanisms
    device: Babbitt and bearing metals
    example: 'PubChem: antimony is used in the manufacture of alloys such as Babbitt metal, hard lead, white metal, type metal and bearing metal.'
    source: pubchem-sb
    where: Uses section, entry on alloys such as Britannia or Babbitt metal
supply:
  - subject: Antimony (mine production)
    abundance: Estimated at 0.2 parts per million in the Earth's crust (Wikipedia)
    producers:
      - country: China
        share_percent: 36.4
        year: 2025
      - country: Russia
        share_percent: 29.1
        year: 2025
      - country: Tajikistan
        share_percent: 20
        year: 2025
      - country: Bolivia
        share_percent: 4.5
        year: 2025
      - country: Burma
        share_percent: 4.1
        year: 2025
    critical_lists:
      - list: EU critical raw materials list (Regulation (EU) 2024/1252, as shown on the European Commission page)
        listed: true
    recycling: 'USGS: recycling supplied 12 % of estimated domestic apparent consumption in 2025, mostly as antimonial lead recovered at secondary lead smelters.'
    substitutes:
      - 'USGS: selected organic compounds and hydrated aluminum oxide substitute for antimony as flame retardants.'
      - 'USGS: chromium, tin, titanium, zinc and zirconium compounds substitute in enamels, paint and pigments; calcium, copper, selenium, sulfur and tin substitute in lead-acid battery alloys.'
    source: usgs-mcs2026-antimony
    where: World Mine Production and Reserves table, 2025e column (world total 110,000 t, rounded). Shares are calculated by Space Mushroom from China 40,000 t, Russia 32,000 t, Tajikistan 22,000 t, Bolivia 5,000 t and Burma 4,500 t over the world total; USGS does not print them. Recycling and Substitutes paragraphs.
  - subject: Unwrought antimony metal and powder imported into the United States
    producers:
      - country: China
        share_percent: 22
        year: 2024
      - country: India
        share_percent: 22
        year: 2024
      - country: Thailand
        share_percent: 20
        year: 2024
      - country: Vietnam
        share_percent: 13
        year: 2024
    critical_lists: []
    source: usgs-mcs2026-antimony
    where: Import Sources (2021–2024) paragraph, unwrought metal and powder; the year is the end of the 2021 to 2024 period as printed
  - subject: United States production and demand
    demand: 'USGS: apparent consumption was 45,000 t in 2025e, and net import reliance was 91 %. Primary smelter output was 700 t and secondary output 3,500 t in 2025e. Mining of antimony began in Montana in 2025; primary metal and oxide were produced from imported feedstock.'
    critical_lists: []
    source: usgs-mcs2026-antimony
    where: Salient Statistics table; Domestic Production and Use paragraph
  - subject: Price and trade events
    demand: 'USGS: the average 2025 metal price was $25 per pound (minimum 99.65 %, cost, insurance and freight). In 2024 China announced export restrictions on antimony in August and banned all exports of antimony to the United States in December.'
    critical_lists: []
    source: usgs-mcs2026-antimony
    where: Salient Statistics table, price row and footnote 3; Events, Trends, and Issues paragraph
documents:
  - title: 'USGS Mineral Commodity Summaries 2026: Antimony'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-antimony.pdf
    year: 2026
  - title: 'PubChem compound record for antimony (CID 5354495): density, melting and boiling points, GHS classification, uses'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/compound/Antimony
    year: 2026
  - title: 'WebElements: antimony physical properties'
    type: database
    url: https://www.webelements.com/antimony/physics.html
    year: 2026
  - title: Goodfellow antimony pellets, 99.5 % purity (CAS 7440-36-0), properties table
    type: datasheet
    url: https://www.goodfellow.com/uk/antimony-pellets-1000180374
    year: 2026
  - title: NIST Atomic Weights and Isotopic Compositions for All Elements, antimony
    type: database
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Sb&all=all&ascii=html
    year: 2026
  - title: 'ICSC 0775: Antimony (metallic), International Chemical Safety Cards'
    type: datasheet
    url: https://www.inchem.org/documents/icsc/icsc/eics0775.htm
    year: 2006
  - title: 'European Commission: critical raw materials list under Regulation (EU) 2024/1252'
    type: report
    url: https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en
    year: 2024
  - title: 'Wikipedia: Antimony (element, occurrence and history only)'
    type: database
    url: https://en.wikipedia.org/wiki/Antimony
    year: 2026
gaps:
  - Tensile strength, yield strength and elongation of antimony were not found in any fetched source, so no strength values are recorded.
  - Brinell hardness (WebElements prints 294 MN m-2) is not entered because its test conditions are not stated on the page. Vickers hardness has no data on the page.
  - WebElements prints a mineral hardness of 3.0 with no units or conditions. Only the Goodfellow Mohs range (3 to 3.3) is recorded.
  - The USGS 2025 final critical minerals list page could not be opened (403 from the server), so the U.S. critical-mineral status of antimony was not verified. Only the EU list is recorded as listed.
  - NIOSH pocket guide (CDC) and the OSHA and ATSDR pages could not be opened, so the exposure limit is taken from ICSC 0775 (2006 card), which may be out of date.
  - No UNS, EN, ASTM, JIS or other grade designation for antimony was found in a fetched source, so identity.designations is empty.
  - The melting, boiling and density values differ between sources (PubChem, Goodfellow, WebElements, ICSC). Each is kept with its own source; none is averaged.
  - Corrosion is qualitative only. No corrosion rate in air, seawater or oxidation kinetics was found in a fetched source.
  - No space-flight, outgassing, atomic oxygen, UV or radiation data for antimony were searched or found in this run. The uses listed are terrestrial.
  - Mine production shares are calculated from USGS 2025e values and are not printed by USGS as percentages.
  - PubChem GHS statements are aggregated from company notifications for 748 reports. The record does not say which antimony form each report covers.
  - Allotrope data (gray, black and yellow antimony) and the transition temperatures between them were not found in a fetched source; PubChem names only gray (hexagonal) and black forms.
sources:
  usgs-mcs2026-antimony:
    title: 'Mineral Commodity Summaries 2026: Antimony (U.S. Geological Survey)'
    id: USGS MCS 2026, February 2026, prepared by Kateryna Klochko
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-antimony.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  pubchem-sb:
    title: 'PubChem compound record: Antimony (CID 5354495), including HSDB, ICSC, NIOSH, ECHA C&L and DOT entries'
    id: CID 5354495; PubChem REST pug_view JSON
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/5354495/JSON
    year: 2026
    kind: database
    license: PubChem (NCBI), public domain; sections attributed to HSDB, ICSC, NIOSH and ECHA
  webelements-sb:
    title: 'WebElements: Antimony, 51 Sb, physical properties (Mark Winter, University of Sheffield)'
    url: https://www.webelements.com/antimony/physics.html
    year: 2026
    kind: database
    license: WebElements, cited not reproduced
  goodfellow-sb:
    title: Goodfellow antimony pellets, 99.5 % purity, CAS 7440-36-0, product properties table
    id: Goodfellow product 1000180374 (UK site)
    url: https://www.goodfellow.com/uk/antimony-pellets-1000180374
    year: 2026
    kind: datasheet
    license: supplier product page, cited not reproduced
  nist-sb-weights:
    title: NIST Atomic Weights and Isotopic Compositions for All Elements, antimony (Sb)
    id: standard atomic weight 121.760(1)
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Sb&all=all&ascii=html
    year: 2026
    kind: database
    license: US government data
  icsc-sb:
    title: ICSC 0775, Antimony (metallic), International Chemical Safety Card (ILO and WHO)
    id: ICSC 0775, October 2006; CAS 7440-36-0, UN 2871
    url: https://www.inchem.org/documents/icsc/icsc/eics0775.htm
    year: 2006
    kind: datasheet
    license: ILO and WHO, cited not reproduced
  ec-crm:
    title: Critical raw materials (European Commission), list under Regulation (EU) 2024/1252
    id: Regulation (EU) 2024/1252
    url: https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en
    year: 2024
    kind: web
    license: European Commission web page
  wikipedia-sb:
    title: Antimony, Wikipedia (element, occurrence and history only)
    url: https://en.wikipedia.org/wiki/Antimony
    year: 2026
    kind: web
    license: CC BY-SA 4.0, linked not reproduced
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 20
  unreachable: 3
  caveats: 6
  note: 'Values were read by an AI assistant on 2026-10-26 from the pages and PDF named in each entry (USGS text extracted from the PDF; PubChem values from its JSON record; Goodfellow values from the product page table). Unreachable: NIOSH pocket guide (access denied), USGS 2025 critical minerals page (403), ATSDR and OSHA pages. Caveats: PubChem and ICSC melting and boiling values disagree with Goodfellow; the GHS notifications do not say which antimony form they cover; the USGS mine shares are calculated; the WebElements resistivity was converted from 40 × 10-8 Ω m; the ICSC card is from 2006; no UNS code was found.'
story:
  risk_groups:
    - title: For people
      lead: Dust and fumes of antimony are hazardous, and the GHS codes in PubChem come from company notifications that do not say which form they cover.
      level: 1
      verdict: Toxic in dust and fumes
      points:
        - label: Antimony as recorded in PubChem
          line: Of 748 company reports to the European chemicals agency, 140 say the substance does not meet GHS criteria. The others give codes for toxic if swallowed (H301), harmful if swallowed or inhaled (H302, H332), suspected cancer (H351) and organ damage with repeated exposure (H373). The signal word is Danger.
        - label: The metal dust
          line: The ICSC card for metallic antimony sets a TLV of 0.5 mg/m3 as an 8-hour average and warns of dermatitis and lung effects with repeated exposure. It applies only to the metal.
    - title: If it fails
      lead: The failure routes in these sources are a dust explosion and the release of stibine gas when antimony meets acid.
      points:
        - label: Dust
          line: Finely dispersed particles form explosive mixtures in air, according to PubChem and ICSC.
        - label: Stibine
          line: PubChem reports that heating or contact with acid releases SbH3 gas, which is toxic.
    - title: Handling and storage
      points:
        - label: Dust
          line: Prevent dispersion of dust. Use a particulate filter respirator adapted to the airborne concentration.
        - label: Incompatible materials
          line: Keep the metal away from oxidizing agents, halogens and acids.
  why: Antimony (Sb, atomic number 51) is a brittle, silvery metalloid. In the United States its largest use is metal products including flame retardants (49 % of 2025 use). Antimonial lead grids are used in lead-acid batteries, and antimony hardens bearing and type metals. The 99.5 % pellet grade has a density of 6.68 g/cm3 at 20 °C and a melting point of 630.7 °C. It conducts heat at 24.4 W/(m·K) at 0 to 100 °C. Its weak points are its toxicity as dust and fume, the stibine gas released with acid, and a supply concentrated in a few countries.
  uses:
    - where: Lead-acid battery grids
      line: Antimonial lead is the main use of antimony in the metal form. USGS reports that recycled antimony comes mostly as antimonial lead from spent lead-acid batteries. Antimonial lead and ammunition took 40 % of U.S. use in 2025.
    - where: Semiconductor devices
      line: PubChem says that high-purity antimony (up to 99.9 %) has a limited but important use in making semiconductor devices.
    - where: Bearing and type metals
      line: PubChem lists antimony in Babbitt metal, hard lead, type metal and bearing metal alloys.
  can_do:
    - label: Melt
      value: 630.7 °C melting point
      benchmark: melting_point
      line: Antimony melts at 630.7 °C in the Goodfellow pellet table. PubChem gives 630.628 °C in its own entry.
    - label: Carry heat
      value: 24.4 W/(m·K)
      benchmark: thermal_conductivity
      line: The 99.5 % pellets conduct heat at 24.4 W/(m·K) at 0 to 100 °C (Goodfellow). WebElements gives 24 W/(m·K) with no temperature.
    - label: Weight
      value: 6.68 g/cm3
      benchmark: density
      line: Density is 6.68 g/cm3 at 20 °C (Goodfellow). PubChem gives 6.68 g/cm3 at 25 °C.
    - label: Stiffness
      value: 54.7 GPa tensile modulus
      benchmark: elastic_modulus
      line: Polycrystalline pellets have a tensile modulus of 54.7 GPa (Goodfellow) and a Young's modulus of 55 GPa (WebElements).
  compare: The values come from different grades and conditions. The Goodfellow pellets are 99.5 % pure, and the WebElements and PubChem values are for the element without a stated grade. Read the table as examples, not as a ranking against other metals.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Thermal conductivity
      benchmark: thermal_conductivity
    - label: Melting point
      benchmark: melting_point
  handling:
    - Specify the grade, because the pellet values (99.5 % Sb) and the element values from reference databases differ.
    - Prevent dust, and use a particulate filter respirator where the airborne level is high.
    - Keep the metal away from acids, oxidizing agents and halogens, because acid can release stibine gas.
  good_for:
    - 'Lead alloys: antimonial lead hardens battery grids and bearing metals (USGS and PubChem).'
    - 'Semiconductor doping: high-purity antimony is used in semiconductor devices (PubChem).'
  watch_out:
    - 'Softness: Mohs hardness 3 to 3.3 (Goodfellow).'
    - 'Toxicity: dust and fume are hazardous, with a TLV of 0.5 mg/m3 for the metal (ICSC).'
    - 'Stibine gas: contact with acid releases a toxic gas (PubChem, ICSC).'
    - 'Supply: China, Russia and Tajikistan provided most of the 2025e mine output, by calculation from USGS (see the supply section).'
    - No tensile strength, outgassing or space-exposure data were found for antimony in this run.
  verdict: Antimony is a hard, brittle metalloid whose main value is as a hardener for lead in batteries and bearing alloys, and as a flame-retardant oxide. Its melting point, density and heat conduction are well recorded. Its weak points are its toxicity as dust, the stibine released with acid, and a supply concentrated in a few countries. The profile lacks tensile, outgassing and space-exposure data.
  recipe:
    line: 'Antimony is a single element (Sb, atomic number 51, group 15). Wikipedia says it is found mainly as the sulfide mineral stibnite (Sb2S3). PubChem records the main route: the metal is made by reducing stibnite with iron scrap or by direct reduction of natural oxide ores. High-purity metal (up to 99.9 %) is made by reducing a purified antimony compound or by thermal decomposition of stibine, and may be refined further by zone melting. The metal from a simple smelting step contains lead, arsenic, sulfur, iron and copper, so it must be refined for commercial use.'
    parts:
      - name: Antimony
        symbol: Sb
        atoms: 1
        atomic_weight: 121.76
        role: The whole material. NIST gives the standard atomic weight as 121.760(1).