Basalt fibre (continuous)

spore: profile
id: basalt-fibre
spore_version: 0.2
family: mineral-fibres
name: Basalt fibre (continuous)
role: continuous reinforcing fibre
category: regolith
type: sintered-regolith
summary: |
  Basalt fibre is a continuous filament drawn from molten basalt rock with essentially no additives. The Knowde listing for Mafic basalt roving gives a density of 2.63 g/cm3 (DIN 65569), a tensile strength of 3000.0 MPa (ASTM D2343) and a modulus of 86 to 90 GPa. Choi and Lee (2015) measured an average tensile strength of 1773 MPa in as-received 12 μm fibre. The sources disagree on density and strength, and no product service temperature was found.
best_for: Stiff, lightweight reinforcement made from a common rock, where the fibre is not loaded off its axis (Choi and Lee 2015 report strength falls sharply at 67.5 degrees)
weakest_at: Strength falls sharply when the fibre is loaded off-axis, and no maximum service temperature or hazard data for the finished product were found
identity:
  formula: 'Melt-drawn filament of crushed and washed basalt rock with essentially no additives (Wikipedia, Basalt fiber). Parent-rock composition from Wikipedia (Basalt, Geochemistry): 45 to 52 wt% SiO2, 2 to 5 wt% total alkalis, 0.5 to 2.0 wt% TiO2, 5 to 14 wt% FeO and 14 wt% or more Al2O3. Oxide analysis of the fibre product itself was not found.'
  source: wiki-basalt
  where: Geochemistry section for the parent rock; the production route is from wiki-basalt-fiber (Manufacturing process section)
tags:
  environments: []
  stresses:
    - extreme-heat
  applications:
    - heat-shields
    - structures
    - propulsion-and-tanks
properties:
  - benchmark: density
    label: Density, basalt fibre (Wikipedia properties table)
    value: 2.67
    unit: g/cm3
    scope: material
    conditions:
      form: basalt fibre as printed in the properties table
      test_method: not printed
    method: Value printed in the properties table of the Wikipedia article
    status: ground
    note: The same article prints 2.65 g/cm3 in its comparison table, and the other two sources give 2.65 and 2.63 g/cm3.
    source: wiki-basalt-fiber
    where: Properties table, Density row
  - benchmark: density
    label: Density, basalt fibre (Wikipedia comparison table)
    value: 2.65
    unit: g/cm3
    scope: material
    conditions:
      form: basalt fibre, as printed in the comparison table
    method: Value printed in the comparison table of the Wikipedia article
    status: ground
    note: Differs from the 2.67 g/cm3 printed earlier in the same article.
    source: wiki-basalt-fiber
    where: Comparison table, Basalt fiber density row
  - benchmark: density
    label: Density, basalt fibre (Mafic roving, DIN 65569)
    value: 2.63
    unit: g/cm3
    scope: material
    conditions:
      form: Mafic basalt direct roving 17 μm
      standard: DIN 65569, as printed
    method: Typical property printed on the Knowde product page
    status: ground
    source: knowde-roving
    where: Typical properties table, Density row
  - benchmark: density
    label: Density, basalt fibre (Choi and Lee 2015)
    value: 2.65
    unit: g/cm3
    scope: material
    conditions:
      form: basalt fibre, as tested in the paper
    method: Value printed in Table 1 and Table 2 of the paper
    status: ground
    source: choi2015
    where: Table 1 and Table 2
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, basalt fibre (Wikipedia properties table)
    value: 2.8
    value_high: 3.1
    bound: range
    unit: GPa
    scope: material
    conditions:
      form: basalt fibre, as printed in the properties table
      test_method: not printed
    method: Range printed in the properties table of the Wikipedia article
    status: ground
    source: wiki-basalt-fiber
    where: Properties table, Tensile strength row
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, basalt fibre (Wikipedia comparison table)
    value: 2.9
    value_high: 3.1
    bound: range
    unit: GPa
    scope: material
    conditions:
      form: basalt fibre, as printed in the comparison table
      test_method: not printed
    method: Range printed in the comparison table of the Wikipedia article
    status: ground
    note: Differs from the 2.8 to 3.1 GPa range printed in the properties table of the same article.
    source: wiki-basalt-fiber
    where: Comparison table, Tensile strength row
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, Mafic roving (ASTM D2343)
    value: 3000
    unit: MPa
    scope: material
    conditions:
      form: Mafic basalt direct roving 17 μm
      test_method: ASTM D2343, as printed
    method: Mechanical property printed on the Knowde product page
    status: ground
    source: knowde-roving
    where: Mechanical properties table, Tensile Strength row
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, as-received basalt fibre (average)
    value: 1773
    unit: MPa
    scope: material
    conditions:
      form: as-received basalt fibre, 12 μm diameter
      statistic: average, as printed in Table 2
    method: Mean printed in Table 2 of the paper (Table 6 gives 1773 ± 349 MPa for 0 degrees)
    status: ground
    note: Section 4.2 gives 1778 MPa for the same 0 degree value, and Table 1 gives a literature range of 3000 to 4840 MPa that the paper says is well above its own measurement.
    source: choi2015
    where: Table 2 (and Table 6)
  - benchmark: elastic_modulus
    label: Elastic modulus, basalt fibre (Wikipedia properties table)
    value: 85
    value_high: 87
    bound: range
    unit: GPa
    scope: material
    conditions:
      form: basalt fibre, as printed in the properties table
      test_method: not printed
    method: Range printed in the properties table of the Wikipedia article
    status: ground
    source: wiki-basalt-fiber
    where: Properties table, Elastic modulus row
  - benchmark: elastic_modulus
    label: Tensile modulus, Mafic roving (ASTM D2343)
    value: 86
    value_high: 90
    bound: range
    unit: GPa
    scope: material
    conditions:
      form: Mafic basalt direct roving 17 μm
      test_method: ASTM D2343, as printed
    method: Mechanical property printed on the Knowde product page
    status: ground
    source: knowde-roving
    where: Mechanical properties table, Tensile Modulus row
  - benchmark: elastic_modulus
    label: Elastic modulus, basalt fibre (Choi and Lee 2015)
    value: 89
    unit: GPa
    scope: material
    conditions:
      form: basalt fibre, as tested in the paper
    method: Value printed in Table 2 of the paper
    status: ground
    source: choi2015
    where: Table 2 and Table 7
  - benchmark: elongation
    label: Elongation at break, basalt fibre (Wikipedia)
    value: 3.15
    unit: '%'
    scope: material
    conditions:
      form: basalt fibre, as printed in the properties table
      test_method: not printed
    method: Value printed in the properties table of the Wikipedia article
    status: ground
    source: wiki-basalt-fiber
    where: Properties table, Elongation at break row
  - benchmark: elongation
    label: Elongation at break, Mafic roving
    value: 3.5
    unit: '%'
    scope: material
    conditions:
      form: Mafic basalt direct roving 17 μm
      test_method: not printed
    method: Mechanical property printed on the Knowde product page
    status: ground
    note: Differs from the 3.15 % printed by Wikipedia; the Knowde listing gives no test method.
    source: knowde-roving
    where: Mechanical properties table, Elongation at Break row
  - benchmark: fibre_diameter
    label: Filament diameter, basalt fibre (Wikipedia)
    value: 10
    value_high: 20
    bound: range
    unit: μm
    scope: material
    conditions:
      form: basalt filament, as printed in the manufacturing section
    method: Range printed in the manufacturing section of the Wikipedia article
    status: ground
    source: wiki-basalt-fiber
    where: Manufacturing process section, Filament diameter
  - benchmark: fibre_diameter
    label: Filament diameter, Mafic roving 17 μm
    value: 13
    value_high: 19
    bound: range
    unit: μm
    scope: material
    conditions:
      form: Mafic basalt direct roving 17 μm (product title gives 17 μm)
    method: Range printed in the fibre diameter table on the Knowde product page
    status: ground
    source: knowde-roving
    where: Fibre diameter table, Filament Diameter row
  - benchmark: fibre_diameter
    label: Filament diameter, as-received basalt fibre (Choi and Lee 2015)
    value: 12
    unit: μm
    scope: material
    conditions:
      form: as-received basalt fibre, as tested in the paper
    method: Value printed in Table 2 of the paper
    status: ground
    source: choi2015
    where: Table 2
  - benchmark: melting_point
    label: Melting temperature of the basalt melt (production)
    value: 1500
    unit: °C
    scope: material
    conditions:
      basis: melt temperature in the production process, as printed as about 1,500 °C (2,730 °F)
      not_a: service temperature of the fibre
    method: Value printed in the manufacturing section of the Wikipedia article
    status: ground
    note: The article gives this as the melting temperature in production. It is not a limit for the finished fibre.
    source: wiki-basalt-fiber
    where: Manufacturing process section, Melting temperature row
  - benchmark: linear_density
    label: Tex value, Mafic roving
    value: 150
    value_high: 900
    bound: range
    unit: tex
    scope: material
    conditions:
      form: Mafic basalt direct roving 17 μm
    method: Range printed in the properties table on the Knowde product page
    status: ground
    note: 'Non-canonical name: linear_density is not in spores/property-canon.yaml.'
    source: knowde-roving
    where: Fibre diameter and linear density table, Tex Value row
  - benchmark: tenacity
    label: Tenacity, Mafic roving (minimum)
    value: 60
    bound: lower
    unit: cN/tex
    scope: material
    conditions:
      form: Mafic basalt direct roving 17 μm
      test_method: not printed
    method: Minimum printed in the mechanical properties table on the Knowde product page
    status: ground
    note: 'Non-canonical name: tenacity is not in spores/property-canon.yaml.'
    source: knowde-roving
    where: Mechanical properties table, Tenacity row
  - benchmark: moisture_content
    label: Moisture content, all sizings (maximum)
    value: 0.1
    bound: upper
    unit: '%'
    scope: material
    conditions:
      form: Mafic basalt direct roving, all sizings
      test_method: not printed
    method: Maximum printed in the typical properties table on the Knowde product page
    status: ground
    note: 'Non-canonical name: moisture_content is not in spores/property-canon.yaml. The page prints max. 0.1 %.'
    source: knowde-roving
    where: Typical properties table, Moisture Content (For all Sizing) row
  - benchmark: strength_retention_at_elevated_temp
    label: Strength retained at up to 600 °C (cited)
    value: 90
    unit: '%'
    scope: material
    conditions:
      temperature_max: 600 °C
      basis: statement citing an earlier reference (the paper's ref. 13); the paper gives no test method
      reference: percentage of room-temperature strength
    method: Figure stated in the Introduction of the paper
    status: ground
    note: Non-canonical name. The paper says the fibre can retain about 90% of its normal-temperature strength up to 600 °C.
    source: choi2015
    where: Section 1 (Introduction)
corrosion:
  - environment: Elevated temperature, up to 600 °C
    headline: Keeps about 90% of its room-temperature strength up to 600 °C, according to Choi and Lee (2015).
    effect: Choi and Lee say basalt fibre can retain about 90% of its normal-temperature strength up to 600 °C, citing an earlier reference. They give no test method. No corrosion, humidity or radiation test on basalt fibre was found in the sources read.
    rating: low
    conditions:
      temperature: up to 600 °C
      basis: statement citing an earlier reference, no test method given
    source: choi2015
    where: Section 1 (Introduction)
risks:
  hazards:
    - text: 'Kamenny Vek SDS for Basfiber continuous basalt fibre products: the products are articles, so they are not classified under GHS, OSHA or EU rules and carry no pictograms. Mechanical stress can generate dust and airborne fibres that may cause discomfort, and skin irritation is possible on contact.'
      ghs: []
      source: basfiber-sds
      where: Sections 2.1 to 2.3, and 4.2 for dust irritation
    - text: 'NextSDS listing for BASALT CONTINUOUS FILAMENT FIBERS (Basaltex group, Gullegem, Belgium): signal word warning, with one hazard statement, H316, which reads basalt continuous filaments can be a mechanical irritant with irritation of the skin, eyes and respiratory tract. The listing adds that no known health effect is connected with long-term use.'
      ghs:
        - H316
      source: nextsds-basalt-filament
      where: Section 02 Hazard Identification, and the Quick Reference block
    - text: 'NextSDS listing for BASALTEX fabrics (Basaltex nv, Wevelgem, Belgium): no signal word. Under the EU calculation method for compositions the product has no labelling obligation. This listing and the filament listing disagree, so the label status is not settled by these sources.'
      ghs: []
      source: nextsds-basaltex
      where: Section 02 Hazard Identification, and Section 15 Regulatory Information
  failure_risks:
    - mode: Off-axis loading
      trigger: Fibre loaded at 67.5 degrees to its axis (Choi and Lee 2015, Table 6)
      consequence: Tensile strength was 302 ± 219 MPa at 67.5 degrees against 1773 ± 349 MPa at 0 degrees. The paper says strength falls by 83% at 67.5 degrees.
      severity: moderate
      source: choi2015
      where: Table 6; Section 4.2
  side_effects: []
  handling:
    - text: Keep moisture low. Knowde gives a maximum moisture content of 0.1 % for all sizings, with no test method printed.
      source: knowde-roving
      where: Typical properties table, Moisture Content row
    - text: Use local suction where dust forms. Wear safety glasses (EN 166) when fibre or dust is airborne, and a dust mask with fine filter (EN 143) or filter P1 (EN 141) at elevated dust levels.
      source: basfiber-sds
      where: Section 7.1 (local suction) and Section 8.2 (personal protection)
    - text: Vacuum settled dust and avoid dust-generating conditions. If sweeping is necessary, use a dust suppressant.
      source: nextsds-basaltex
      where: Section 06 Accidental Release Measures
  mitigations: []
uses:
  - application: heat-shields
    device: Heat protection (product not named)
    example: Wikipedia lists heat protection among the uses of basalt fibre, without naming a product or a temperature limit.
    source: wiki-basalt-fiber
    where: Uses section, list of uses
  - application: structures
    device: Rebar for concrete, including pultruded rebar
    example: Wikipedia lists basalt fibre rebar for concrete, including pultruded rebar, and chopped strand for concrete reinforcement.
    source: wiki-basalt-fiber
    where: Uses section, list of uses
  - application: propulsion-and-tanks
    device: Compressed natural gas cylinders and pipes; high-pressure vessels (terrestrial)
    example: Wikipedia lists basalt fibre for compressed natural gas cylinders and pipes and for high-pressure vessels. These are ground uses, not space hardware.
    source: wiki-basalt-fiber
    where: Uses section, list of uses
supply:
  - subject: Basalt rock (feedstock)
    abundance: 'USGS: stone resources are plentiful throughout the world. No world production total for crushed stone is reported, because most countries do not report production. Traprock was 6% of 2025 US crushed stone output.'
    producers: []
    critical_lists: []
    substitutes: []
    source: usgs-mcs2026-stone
    where: Domestic Production and Use (2025 shares); World Resources and footnote 7. The chapter does not say how much of the traprock is basalt.
  - subject: Continuous basalt fibre, producer in Russia
    producers:
      - country: Russia
    critical_lists: []
    source: basfiber-sds
    where: 'Section 1.3, supplier details: Kamenny Vek LLC, Dubna, Moscow region (Basfiber trademark). No production share is given.'
  - subject: Continuous basalt fibre, producer in Belgium
    producers:
      - country: Belgium
    critical_lists: []
    source: nextsds-basaltex
    where: 'Section 01 Identification: manufacturer BASALTEX nv, Wevelgem. The filament listing names Basaltex group (Masureel Veredeling nv, Gullegem). No production share is given.'
media: []
documents:
  - title: Bonding Properties of Basalt Fiber and Strength Reduction According to Fiber Orientation (open access)
    type: paper
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC5455386
    year: 2015
  - title: Mafic basalt direct roving 17 μm, Knowde product page (typical and mechanical property tables)
    type: datasheet
    url: https://www.knowde.com/stores/mafic/products/mafic-basalt-direct-roving-17-m
    year: 2026
  - title: Safety Data Sheet, Continuous basalt fiber products (Basfiber, Kamenny Vek LLC), revision 2
    type: sds
    url: https://basfiber.com/system/storage/download/Safety_Data_Sheet.pdf
    year: 2017
  - title: BASALTEX fabrics, safety data sheet listing (NextSDS)
    type: sds
    url: https://nextsds.com/sds/en/281331501269204/basaltex
    year: 2026
  - title: BASALT CONTINUOUS FILAMENT FIBERS, safety data sheet listing (NextSDS)
    type: sds
    url: https://nextsds.com/sds/en/281331501269531/basalt-fibre-components-yarns-rovings-fabrics-non-woven-mats
    year: 2026
  - title: Mineral Commodity Summaries 2026, Stone (Crushed)
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-stone-crushed.pdf
    year: 2026
gaps:
  - 'Supply: no producer shares, world production or critical-mineral listing for basalt fibre were found. Producers are named without shares (Kamenny Vek in Russia; Basaltex group in Belgium). The USGS crushed-stone chapter gives no world total and does not identify basalt. The EU critical raw materials list was not checked.'
  - No maximum service temperature, softening temperature or continuous-use limit for the finished fibre was found. Knowde and Wikipedia both leave it out.
  - The Mafic technical data sheet (Knowde document 292451) returned an empty page, so no value from it is used.
  - 'The Mafic safety data sheet: the Knowde SDS page gave only a title and a PDF link (media.knowde.dev), and the PDF download returned an empty file. Hazard entries come from three other SDS listings (Kamenny Vek; two NextSDS listings for Basaltex-group products), and they disagree. The Kamenny Vek SDS gives no data for acute toxicity or irritation, so no toxicology value is recorded.'
  - The manufacturer website mafic.com redirects to a parked-domain page and was not used.
  - 'Two open papers from the Wikipedia reference list could not be read: Soares et al. 2016 (DOI redirect returned only ''Redirecting'') and De Fazio 2011 (ENEA PDF returned an HTML page with a certificate error).'
  - 'Fibre composition: no oxide analysis for the finished fibre was found. The parent-rock composition from Wikipedia is context only.'
  - 'Corrosion, humidity, radiation and vacuum behaviour: no test was found. Only the strength-retention statement from Choi and Lee (2015) was read.'
  - 'Designation: no UNS, EN, ASTM or DIN grade number for basalt fibre was found. ASTM D2343 and DIN 65569 are test methods named on the Knowde page, not designations of the fibre.'
  - 'Chang''e 5 use: Wikipedia lists a cloth ''linked to Chang''e 5'' with no detail. The mission document was not read, so this use is left out.'
  - 'Non-canonical property names: fibre_diameter, linear_density, tenacity, moisture_content and strength_retention_at_elevated_temp are not in spores/property-canon.yaml.'
  - 'Disagreement: density is 2.63 (Knowde, DIN 65569), 2.65 (Choi and Lee; Wikipedia comparison table) and 2.67 g/cm3 (Wikipedia properties table). Tensile strength is 1773 MPa (Choi and Lee, average of as-received 12 μm fibre), 2.8 to 3.1 GPa (Wikipedia) and 3000.0 MPa (Knowde, ASTM D2343).'
  - 'Melting and softening: the Kamenny Vek SDS prints approx. 1050 °C as the softening point of basalt, and the Basaltex listing prints a melting point of 1450±150 °C and a softening point of 1050±100 °C. These are raw-rock or unstated-basis values for the fibre, so they are not recorded as properties and are not a service temperature.'
  - Eight sources are cited. Soares 2016 and De Fazio 2011 could not be opened, and the MDPI reviews on basalt fibre composition were blocked to this run.
sources:
  wiki-basalt-fiber:
    title: Basalt fiber (Wikipedia article)
    id: Wikipedia, English edition, accessed 2026-11-01
    url: https://en.wikipedia.org/wiki/Basalt_fiber
    year: 2026
    kind: web
    license: Wikipedia text licence; cited, not reproduced
  knowde-roving:
    title: Mafic basalt direct roving 17 μm (Knowde storefront, Mafic product page)
    id: Mafic product listed on Knowde, accessed 2026-11-01
    url: https://www.knowde.com/stores/mafic/products/mafic-basalt-direct-roving-17-m
    year: 2026
    kind: web
    license: Product listing; cited, not reproduced
  wiki-basalt:
    title: Basalt (Wikipedia article)
    id: Wikipedia, English edition, accessed 2026-11-01
    url: https://en.wikipedia.org/wiki/Basalt
    year: 2026
    kind: web
    license: Wikipedia text licence; cited, not reproduced
  choi2015:
    title: Bonding Properties of Basalt Fiber and Strength Reduction According to Fiber Orientation
    id: doi:10.3390/ma8105335 (Materials 8(10), 6719-6727, PMC5455386)
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC5455386
    year: 2015
    kind: paper
    license: Open access (MDPI); licence not checked in this run
  basfiber-sds:
    title: Safety Data Sheet, Continuous basalt fiber products (Basfiber, Kamenny Vek LLC)
    id: Revision 2, dated 30 September 2015 and 25 October 2017 (as printed)
    url: https://basfiber.com/system/storage/download/Safety_Data_Sheet.pdf
    year: 2017
    kind: datasheet
    license: Manufacturer SDS; cited, not reproduced
  nextsds-basaltex:
    title: BASALTEX fabrics, safety data sheet listing (NextSDS)
    id: BASALTEX nv, Wevelgem, Belgium (listing read 2026-11-01)
    url: https://nextsds.com/sds/en/281331501269204/basaltex
    year: 2026
    kind: datasheet
    license: Listing; cited, not reproduced
  nextsds-basalt-filament:
    title: BASALT CONTINUOUS FILAMENT FIBERS, safety data sheet listing (NextSDS)
    id: Basaltex group, Masureel Veredeling nv, Gullegem, Belgium (listing read 2026-11-01)
    url: https://nextsds.com/sds/en/281331501269531/basalt-fibre-components-yarns-rovings-fabrics-non-woven-mats
    year: 2026
    kind: datasheet
    license: Listing; cited, not reproduced
  usgs-mcs2026-stone:
    title: Mineral Commodity Summaries 2026, Stone (Crushed)
    id: USGS, doi:10.3133/mcs2026 (Stone (Crushed) chapter, February 2026)
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-stone-crushed.pdf
    year: 2026
    kind: report
    license: US Government work
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 21
  unreachable: 3
  caveats: 4
  note: 'Read by an AI assistant on 2026-11-01: 21 property values read from 3 fetched pages and 1 paper. Deepen pass on the same date added 4 sources (a supplier SDS from Kamenny Vek, two NextSDS listings for Basaltex-group products, and the USGS crushed-stone chapter) for hazards and supply. Soares 2016, De Fazio 2011 and the Mafic datasheet and SDS could not be read.'
story:
  recipe:
    line: Basalt fibre is made by melting crushed and washed basalt rock in one stage, then extruding the melt through small nozzles to form continuous filaments. Wikipedia says the process uses essentially no additives, so the fibre keeps the rock's own oxides.
    parts:
      - name: Basalt rock
        role: 'The only feedstock: crushed and washed rock from a selected quarry, with essentially no additives (Wikipedia, Basalt fiber).'
      - name: Silica (SiO2)
        role: The main oxide of basalt rock, 45 to 52 wt% in the parent rock (Wikipedia, Basalt). Fibre-specific oxide analysis was not found.
  risk_groups:
    - title: For people
      level: 0
      verdict: Conflicting supplier data
      lead: Three supplier safety data sheet listings were read in this run, and they disagree. The Kamenny Vek SDS says the article is not classified under GHS. One NextSDS listing gives a warning with H316. The other gives no signal word.
      points:
        - label: Hazard data
          line: Dust and fibre can irritate skin, eyes and airways under mechanical stress, per the SDS listings. The sources do not agree on a hazard label, so treat the classification as unsettled.
    - title: Handling
      points:
        - label: Moisture
          line: Knowde gives a maximum moisture content of 0.1 % for all sizings, with no test method printed.
        - label: Fibre direction
          line: Strength drops sharply when the fibre is loaded off its axis. Choi and Lee (2015) report an 83% fall at 67.5 degrees.
  why: Basalt fibre is a continuous mineral fibre drawn from molten basalt rock. It is the nearest Earth analogue to a fibre drawn from molten regolith. Its raw material is a common rock, and the production route uses essentially no additives. The sources we could open give density, tensile strength and modulus that agree in order of magnitude but not in value.
  uses:
    - where: Heat protection
      line: Wikipedia lists heat protection among the uses of basalt fibre. The article names no product and gives no temperature limit for a finished product.
    - where: Concrete reinforcement
      line: Wikipedia lists basalt fibre rebar for concrete, including pultruded rebar, and chopped strand for concrete reinforcement.
    - where: Pressure vessels (terrestrial)
      line: Wikipedia lists basalt fibre for compressed natural gas cylinders and pipes and for high-pressure vessels. These are ground uses, not space hardware.
  can_do:
    - label: Stiffness
      benchmark: elastic_modulus
      line: Elastic modulus is 85 to 87 GPa in Wikipedia, 86 to 90 GPa in the Knowde listing (ASTM D2343) and 89 GPa in Choi and Lee (2015), Table 2.
    - label: Tensile strength
      benchmark: ultimate_tensile_strength
      line: The sources disagree. Wikipedia gives 2.8 to 3.1 GPa and Knowde gives 3000.0 MPa (ASTM D2343). A lab test on 12 μm fibre averaged 1773 MPa in Choi and Lee (2015), Table 2. Both are shown because the sources do not agree.
    - label: Heat
      value: About 90% strength at 600 °C
      line: Choi and Lee (2015) say the fibre can keep about 90% of its room-temperature strength up to 600 °C, citing an earlier reference. They give no test method.
  compare: Basalt fibre has an elastic modulus of 85 to 90 GPa and a density of 2.63 to 2.67 g/cm3 across the sources read. No glass or carbon fibre values were read in this run, so this profile does not rank basalt fibre against them.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Tensile strength
      benchmark: ultimate_tensile_strength
    - label: Elastic modulus
      benchmark: elastic_modulus
  handling:
    - Keep the roving dry. The maximum moisture content for all sizings is 0.1 % (Knowde).
    - Do not load the fibre off its axis. Choi and Lee (2015) report an 83% strength fall at 67.5 degrees.
    - Use local suction where dust forms. Wear safety glasses (EN 166) when fibre or dust is airborne, and a dust mask with fine filter (EN 143) or filter P1 (EN 141) at elevated dust levels, per the Kamenny Vek SDS.
  good_for:
    - Heat tolerance. Choi and Lee (2015) report about 90% strength retained up to 600 °C, citing an earlier reference.
    - Stiffness. The sources read give a modulus of 85 to 90 GPa.
  watch_out:
    - The sources disagree. Density is 2.63, 2.65 or 2.67 g/cm3, and tensile strength ranges from 1773 MPa to 3.1 GPa.
    - Strength falls sharply off-axis. Choi and Lee (2015) report an 83% fall at 67.5 degrees.
    - No product service temperature was found. Knowde and Wikipedia both leave it out.
  verdict: Basalt fibre is a rock-based reinforcement with a modulus of about 85 to 90 GPa. The sources we could open disagree on strength and density, the supplier safety listings disagree on a hazard label, and we found no service-temperature limit, so this profile is a draft.