spore: profile
id: olivine-forsterite
spore_version: 0.2
family: regolith
name: Olivine (forsterite, Mg2SiO4)
role: Silicate mineral in mare basalt; a named phase in the lunar simulants JSC-1A and LMS-1
category: regolith
type: lunar-simulants
summary: 'Forsterite (Mg2SiO4), the magnesium end member of the olivine group, has a calculated bulk density of 3.25 g/cm3 (WebMineral, Calculated Properties) and a calculated refractive index (Ncalc) of 1.65 to 1.68 (WebMineral, Optical Properties). Olivine is a named phase in two lunar simulants: NASA lists 9.0% olivine in the modal mineralogy of JSC-1A, and the CLASS Exolith Lab lists 11.1 wt.% in LMS-1. No measured density with a printed unit, no melting point, and no space-environment or processing data for forsterite were found in the sources read for this profile.'
best_for: Reference values for forsterite, and the olivine share of two lunar simulants (9.0% in JSC-1A, 11.1 wt.% in LMS-1)
weakest_at: No measured density with a printed unit, no melting point, and no flight, space-environment or ISRU data in the sources read in this run
identity:
  formula: Mg2SiO4
  crystal_system: orthorhombic
  space_group: Pbnm
  source: webmineral-forsterite
  where: Crystallography table (WebMineral); the Handbook of Mineralogy prints the space group as P bnm (synthetic)
tags:
  environments: []
  stresses: []
  applications:
    - rovers-and-surface-systems
    - thermal-control
properties:
  - benchmark: density
    label: Bulk density, forsterite (calculated, as printed by WebMineral)
    value: 3.25
    unit: g/cm3
    scope: material
    conditions:
      basis: bulk density from electron density, listed under Calculated Properties on the page
      unit_in_source: gm/cc
      mineral: forsterite, Mg2SiO4
    method: Calculated value printed on WebMineral; the page prints the unit as gm/cc, which is the same unit as g/cm3
    status: calculated
    source: webmineral-forsterite
    where: Calculated Properties, Bulk Density (Electron Density) row
  - benchmark: refractive_index
    label: Refractive index, calculated (Ncalc), forsterite
    value: 1.65
    value_high: 1.68
    bound: range
    unit: '-'
    scope: material
    conditions:
      basis: Ncalc as printed on WebMineral; the page gives no wavelength
      mineral: forsterite
    method: Calculated value printed on WebMineral, Optical Properties
    status: calculated
    source: webmineral-forsterite
    where: Optical Properties, Ncalc row
  - benchmark: refractive_index
    label: Refractive index range printed as a, WebMineral
    value: 1.636
    value_high: 1.73
    bound: range
    unit: '-'
    scope: material
    conditions:
      basis: range printed for index a; the page gives no wavelength or sample
      mineral: forsterite
    method: Range printed on WebMineral, Optical Properties
    status: ground
    source: webmineral-forsterite
    where: Optical Properties, Refractive index a row
  - benchmark: refractive_index
    label: Refractive index range printed as b, WebMineral
    value: 1.65
    value_high: 1.739
    bound: range
    unit: '-'
    scope: material
    conditions:
      basis: range printed for index b; the page gives no wavelength or sample
      mineral: forsterite
    method: Range printed on WebMineral, Optical Properties
    status: ground
    source: webmineral-forsterite
    where: Optical Properties, Refractive index b row
  - benchmark: refractive_index
    label: Refractive index range printed as g, WebMineral
    value: 1.669
    value_high: 1.772
    bound: range
    unit: '-'
    scope: material
    conditions:
      basis: range printed for index g; the page gives no wavelength or sample
      mineral: forsterite
    method: Range printed on WebMineral, Optical Properties
    status: ground
    source: webmineral-forsterite
    where: Optical Properties, Refractive index g row
  - benchmark: birefringence
    label: Birefringence range, WebMineral
    value: 0.033
    value_high: 0.042
    bound: range
    unit: '-'
    scope: material
    conditions:
      basis: range printed on the page; the page does not state the wavelength or the definition used
      mineral: forsterite
    method: Range printed on WebMineral, Optical Properties
    status: ground
    source: webmineral-forsterite
    where: Optical Properties, Birefringence row
  - benchmark: hardness
    label: Hardness, Handbook of Mineralogy
    value: 7
    unit: '-'
    scope: material
    conditions:
      scale: not named in the source; the Handbook prints Hardness = 7
      mineral: forsterite
    method: Single value printed in the Physical Properties block of the Handbook
    status: ground
    source: handbook-forsterite
    where: Physical Properties block
  - benchmark: hardness
    label: Hardness range, WebMineral
    value: 6
    value_high: 7
    bound: range
    unit: '-'
    scope: material
    conditions:
      scale: not named; the page pairs the range with orthoclase and quartz as reference minerals
      mineral: forsterite
    method: Range printed on WebMineral, Physical Properties
    status: ground
    source: webmineral-forsterite
    where: Physical Properties, Hardness row
  - benchmark: molecular_weight
    value: 140.69
    unit: gm
    scope: material
    conditions:
      basis: molecular weight of Mg2SiO4 as printed
      mineral: forsterite
    method: Printed as 140.69 gm in the Composition section of WebMineral; the unit is kept as printed
    status: calculated
    source: webmineral-forsterite
    where: Composition section, Molecular weight
  - benchmark: mgo_content
    label: MgO, theoretical oxide content of forsterite
    value: 57.29
    unit: '%'
    scope: material
    conditions:
      basis: theoretical stoichiometric composition of Mg2SiO4, not a measured analysis
      oxide: MgO
    method: Composition section of WebMineral, Magnesium row
    status: calculated
    source: webmineral-forsterite
    where: Composition section, Magnesium row (57.29 % MgO)
  - benchmark: sio2_content
    label: SiO2, theoretical oxide content of forsterite
    value: 42.71
    unit: '%'
    scope: material
    conditions:
      basis: theoretical stoichiometric composition of Mg2SiO4, not a measured analysis
      oxide: SiO2
    method: Composition section of WebMineral, Silicon row
    status: calculated
    source: webmineral-forsterite
    where: Composition section, Silicon row (42.71 % SiO2)
  - benchmark: olivine_modal_abundance
    label: Olivine in JSC-1A, modal mineralogy
    value: 9
    unit: '%'
    scope: material
    conditions:
      material: JSC-1A lunar regolith simulant, crushed from basaltic ash; olivine is one phase of the simulant, not pure forsterite
      basis: abundance column of the modal mineralogy table, reference [12] as printed
    method: Modal mineralogy printed on the NASA ARES page
    status: ground
    source: ares-jsc1a
    where: Mineralogy, Modal Mineralogy table, Olivine row
  - benchmark: olivine_modal_abundance
    label: Olivine in LMS-1, mineralogy table
    value: 11.1
    unit: wt.%
    scope: material
    conditions:
      material: LMS-1 lunar mare simulant; olivine is one phase of the simulant, not pure forsterite
      column: Wt.% as printed
    method: Mineralogy table on the CLASS Exolith Lab LMS-1 page
    status: ground
    source: class-lms-1
    where: Mineralogy table, Exolith Simulant LMS-1 section, Olivine row
corrosion:
  - environment: Aqueous acidic solution (oxalic acid, pH 0 to 7, 25°C), laboratory dissolution test
    headline: Forsterite dissolves more slowly as water activity falls, according to a 2007 Virginia Tech dissertation.
    effect: The dissertation abstract states 'However, decreasing aH2O slows forsterite dissolution rates.' It attributes this to water acting as a ligand in the dissolution process. The experiments used oxalic acid solutions, not humid air, so this is a dissolution result and not a measured corrosion rate.
    rating: low
    conditions:
      basis: laboratory dissolution kinetics in oxalic acid solutions over a pH range of 0 to 7 at 25°C, as printed in the abstract
      material: forsterite
      test: no exposure time or numeric dissolution rate is quoted in this entry
    source: olsen2007
    where: Abstract, VTechWorks record handle 10919/28213
risks:
  hazards:
    - text: PubChem's GHS summary for the record named Olivine (CID 71586774, formula Fe2Mg8O20Si5) gives H319, Causes serious eye irritation, for 95.7% of notifications, with the signal word Warning. 22 of 23 reports gave a hazard code, and 1 of 23 reports (4.3%) says the record does not meet GHS hazard criteria.
      ghs:
        - H319
      source: pubchem-olivine
      where: Safety and Hazards, Hazards Identification, GHS Classification (CID 71586774)
    - text: PubChem lists no pictogram for this record and gives the precautionary codes P264+P265, P280, P305+P351+P338 and P337+P317. The wording of these statements was not read in this run.
      ghs: []
      source: pubchem-olivine
      where: Safety and Hazards, GHS Classification, Precautionary Statement Codes
    - text: PubChem's uses section describes this sand as having low levels of free silica and suggests it as a less injurious substitute for silica quartz in foundries (ChemIDplus).
      ghs: []
      source: pubchem-olivine
      where: Use and Manufacturing, Uses
  failure_risks: []
  side_effects: []
  handling:
    - text: No supplier safety data sheet for pure forsterite was read in this run. The hazard codes above come from a PubChem record for a mixed magnesium-iron olivine.
      source: pubchem-olivine
      where: Safety and Hazards (CID 71586774)
  mitigations: []
uses:
  - application: rovers-and-surface-systems
    device: Lunar mare simulant LMS-1 (ground test material)
    example: The CLASS Exolith Lab LMS-1 mineralogy table lists olivine at 11.1 wt.%.
    source: class-lms-1
    where: Mineralogy table, Exolith Simulant LMS-1 section
  - application: rovers-and-surface-systems
    device: JSC-1A lunar regolith simulant (ground test material)
    example: NASA's ARES page says JSC-1A is crushed from basaltic ash, and its modal mineralogy lists olivine at 9.0%.
    source: ares-jsc1a
    where: Source material text; Mineralogy, Modal Mineralogy table
  - application: thermal-control
    device: Refractory linings (industrial use, not a space application)
    example: USGS says the remaining magnesium compounds used in the United States went to refractories, in the form of dead-burned magnesia, fused magnesia and olivine.
    source: usgs-mcs2026-magnesium
    where: Domestic Production and Use, second paragraph
supply:
  - subject: Magnesium (the metal in olivine; the critical-list entries name magnesium, not olivine)
    abundance: 'USGS: resources of dolomite, forsterite, magnesium-bearing evaporite minerals and magnesia-bearing brines are estimated at billions of tons. No tonnage for forsterite alone is printed.'
    producers: []
    critical_lists:
      - list: USGS 2025 List of Critical Minerals (magnesium listed as Magnesium, used in metal alloys)
        listed: true
      - list: EU critical raw materials list (Regulation (EU) 2024/1252; the page lists Magnesium)
        listed: true
    recycling: 'USGS magnesium chapter: some magnesia-based refractories are recycled as construction aggregate, reused in refractory, and as foundry sand. Olivine recycling is not mentioned.'
    substitutes:
      - 'USGS: alumina, chromite and silica substitute for magnesia in some refractory applications. Olivine is not named.'
    source: usgs-mcs2026-magnesium
    where: 'World Resources; Recycling; Substitutes; Domestic Production (one company in Washington sold and processed stockpiled olivine). Critical lists: usgs-crit2025 and ec-crm pages.'
media: []
documents:
  - title: 'Handbook of Mineralogy: Forsterite (Mineral Data Publishing, version 1.2)'
    type: database
    url: https://handbookofmineralogy.org/pdfs/forsterite.pdf
    year: 2001
  - title: 'WebMineral: Forsterite data page'
    type: database
    url: https://www.webmineral.com/data/Forsterite.shtml
  - title: 'USGS Mineral Commodity Summaries 2026: Magnesium Compounds'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-magnesium-compounds.pdf
    year: 2026
  - title: 'PubChem: Olivine (CID 71586774), GHS classification summary'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/compound/71586774
  - title: 'NASA ARES: JSC-1 and JSC-1A lunar regolith simulant project page'
    type: report
    url: https://ares.jsc.nasa.gov/projects/simulants/jsc-1-1a.html
  - title: 'Olsen (2007), Forsterite Dissolution Kinetics: Applications and Implications for Chemical Weathering, Virginia Tech dissertation'
    type: paper
    url: https://vtechworks.lib.vt.edu/handle/10919/28213
    year: 2007
gaps:
  - Melting point not found in any source the brief allows. WebMineral and the Handbook print none. Wikipedia gives almost 1,900 degC, but it is not used because the brief limits Wikipedia to composition and history.
  - No measured density with a printed unit was found for forsterite. The Handbook prints D(meas.) 3.275 and D(calc.) 3.271 with no unit, and WebMineral prints 3.21 to 3.33 with no unit, so these are left out.
  - Unit cell lengths a, b and c and the strongest X-ray d-spacings are printed without a unit on both pages, so they are left out.
  - The Handbook's Mogok chemical analysis (SiO2, FeO, MgO) prints no unit, so it is left out.
  - The Handbook's three refractive indices are printed with symbols that did not survive text extraction, so they are left out. WebMineral's a, b and g ranges are used instead.
  - Hardness scale is not named in the Handbook; the unit is recorded as -.
  - Corrosion in humid air and long-term ageing of forsterite or olivine were not found. The one corrosion entry is an aqueous dissolution result from a 2007 dissertation, in oxalic acid at 25°C, not a humid-air test.
  - Vacuum, radiation, thermal-cycling and other space-environment data for olivine were not found.
  - Failure modes, side effects and mitigations were not found, so those sections are empty.
  - The 13.7 wt% olivine figure for MGS-1 (Mars Global Simulant) is not verified. No MGS-1 source was read in this run.
  - ISRU oxygen and magnesium extraction from olivine is not sourced. The brief's statement that olivine is used in such studies stays unverified.
  - Atomic weights were not read on a fetched page, so the recipe gives atom counts from the formula only.
  - No country shares for olivine or forsterite were printed in the pages read. The USGS magnesium table covers magnesite production, not olivine.
  - Crustal abundance of forsterite or olivine was not found.
  - Hazard data come from PubChem's record named Olivine (CID 71586774, formula Fe2Mg8O20Si5), a mixed magnesium-iron olivine, not pure forsterite. No forsterite safety data sheet was read.
  - The PubChem name lookup for forsterite returned no compound, so the forsterite record itself was not read.
  - CAS number was not read on a fetched page.
  - No abbreviation for olivine or forsterite was found in the sources read.
  - Olivine itself is not an entry on the USGS or EU critical lists read; the listing applies to magnesium.
  - 'Custom property names not in spores/property-canon.yaml: molecular_weight, mgo_content, sio2_content, hardness, birefringence, olivine_modal_abundance.'
  - No media added; no image was read or licence checked in this run.
  - Web search was unavailable after the first calls in this run, so no further sources could be searched for.
sources:
  webmineral-forsterite:
    title: 'Forsterite: mineral data (WebMineral)'
    id: WebMineral forsterite data page
    url: https://www.webmineral.com/data/Forsterite.shtml
    kind: web
    license: Web page; licence not stated on the page read
  handbook-forsterite:
    title: Forsterite, Handbook of Mineralogy
    id: Mineral Data Publishing, version 1.2, copyright 2001
    url: https://handbookofmineralogy.org/pdfs/forsterite.pdf
    year: 2001
    kind: handbook
    license: All rights reserved by Mineral Data Publishing; cited, not reproduced
  wikipedia-olivine:
    title: Olivine (Wikipedia)
    id: en.wikipedia.org, Olivine
    url: https://en.wikipedia.org/wiki/Olivine
    kind: web
    license: CC BY-SA (Wikipedia text); cited for composition and history only
  usgs-mcs2026-magnesium:
    title: Mineral Commodity Summaries 2026, Magnesium Compounds
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-magnesium-compounds.pdf
    year: 2026
    kind: report
    license: Public domain (USGS)
  usgs-crit2025:
    title: About the 2025 List of Critical Minerals (USGS)
    id: Final 2025 List of Critical Minerals
    url: https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals
    year: 2025
    kind: web
    license: Public domain (USGS)
  ec-crm:
    title: Critical raw materials (European Commission)
    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
  pubchem-olivine:
    title: PubChem compound record, Olivine (CID 71586774)
    id: CID 71586774
    url: https://pubchem.ncbi.nlm.nih.gov/compound/71586774
    kind: database
    license: Public domain (NCBI)
  ares-jsc1a:
    title: JSC-1 and JSC-1A lunar regolith simulant, NASA ARES Simulants project page
    id: NASA Exploration Research and Simulation (ARES) simulants project
    url: https://ares.jsc.nasa.gov/projects/simulants/jsc-1-1a.html
    kind: web
    license: NASA web page; licence not stated on the page read
  class-lms-1:
    title: LMS-1 Lunar Mare Simulant, CLASS Exolith Lab (University of Central Florida)
    url: https://sciences.ucf.edu/class/simulant_lunarmare/
    kind: web
    license: University web page; licence not checked in this run
  olsen2007:
    title: 'Forsterite Dissolution Kinetics: Applications and Implications for Chemical Weathering'
    id: Olsen, A. A. (2007), Virginia Tech doctoral dissertation, VTechWorks handle 10919/28213
    url: https://vtechworks.lib.vt.edu/handle/10919/28213
    year: 2007
    kind: paper
    license: Virginia Tech thesis repository; licence not checked in this run
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 13
  unreachable: 0
  caveats: 3
  note: Written by an AI assistant on 2026-11-01 from nine pages fetched in this run. Web search was unavailable after the first calls, so MGS-1, ISRU, corrosion and melting-point sources were not found. A corrosion entry from the Olsen (2007) dissertation abstract was added in a later pass. verify-values then found 13 of 13 values in their sources.
story:
  recipe:
    line: 'Forsterite is Mg2SiO4: two magnesium atoms, one silicon atom and four oxygen atoms per formula unit (WebMineral and the Handbook of Mineralogy). Natural olivine is a series between forsterite and fayalite, Fe2SiO4, the iron end member (Wikipedia).'
    parts:
      - name: Magnesium
        symbol: Mg
        role: The main metal in forsterite. Forsterite is the magnesium end member of the olivine group.
      - name: Silicon
        symbol: Si
        role: The silicon atom in the formula Mg2SiO4.
      - name: Oxygen
        symbol: O
        role: The four oxygen atoms per formula unit.
  risk_groups:
    - title: For people
      level: 0
      verdict: Eye irritant under GHS in the PubChem record
      lead: The PubChem record for olivine is an eye irritant in most reports. That record is a mixed magnesium-iron silicate, not pure forsterite, and no forsterite safety data sheet was read in this run.
      points:
        - label: Eyes
          line: PubChem's GHS summary gives H319, causes serious eye irritation, for 95.7% of notifications, with the signal word Warning.
        - label: Notifications
          line: 22 of 23 reports gave a hazard code. 1 of 23 reports (4.3%) says the record does not meet GHS hazard criteria.
        - label: Dust
          line: PubChem's uses section describes low levels of free silica in this sand. No dust exposure limit was read in this run.
    - title: Handling and storage
      lead: The sources read give only short precautionary codes.
      points:
        - label: Precautionary codes
          line: PubChem lists P264+P265, P280, P305+P351+P338 and P337+P317 for the olivine record. The wording of these statements was not read in this run.
        - label: Storage
          line: No storage or incompatibility advice for pure forsterite was read in this run.
  why: 'Forsterite (Mg2SiO4) is the magnesium end member of the olivine group, and fayalite (Fe2SiO4) is the iron end member (Wikipedia). The Handbook of Mineralogy lists its occurrence in mafic and ultramafic igneous rocks. Wikipedia''s olivine page shows an olivine basalt from the Moon, collected by the Apollo 15 crew. Two lunar simulant pages read for this profile list olivine as a mineral phase: 9.0% of JSC-1A by modal mineralogy, and 11.1 wt.% of LMS-1.'
  uses:
    - where: Ground test simulants
      line: NASA's ARES page says JSC-1A is crushed from basaltic ash, and lists olivine at 9.0% in its modal mineralogy. The CLASS Exolith Lab page for LMS-1 lists olivine at 11.1 wt.%.
    - where: Refractories
      line: The US Geological Survey says that the remaining magnesium compounds used in the United States went to refractories, in the form of dead-burned magnesia, fused magnesia and olivine.
  can_do:
    - label: Density
      benchmark: density
      line: WebMineral prints a calculated bulk density of 3.25 g/cm3 for forsterite. No measured density with a printed unit was found in the sources read.
    - label: Refractive index
      benchmark: refractive_index
      line: WebMineral gives a calculated refractive index (Ncalc) of 1.65 to 1.68, and printed ranges of 1.636 to 1.73 for index a, 1.65 to 1.739 for index b and 1.669 to 1.772 for index g.
    - label: Hardness
      benchmark: hardness
      line: The Handbook of Mineralogy gives a hardness of 7, and WebMineral gives 6 to 7. Neither page names the scale.
    - label: Oxide split
      benchmark: mgo_content
      line: The theoretical composition is 57.29% MgO and 42.71% SiO2, per WebMineral's stoichiometric composition.
    - label: Simulant content
      benchmark: olivine_modal_abundance
      line: Olivine is 9.0% of the modal mineralogy of JSC-1A (NASA ARES) and 11.1 wt.% of LMS-1 (CLASS Exolith Lab).
  compare: 'Olivine is a named phase in the two lunar simulants read here: 9.0% of JSC-1A by modal mineralogy and 11.1 wt.% of LMS-1 by the CLASS mineralogy table. The forsterite end member is the magnesium-rich form, with a theoretical 57.29% MgO and a calculated bulk density of 3.25 g/cm3. A density comparison with other regolith materials was not made in this run, because their figures were not read here.'
  compare_rows:
    - label: Bulk density, calculated (g/cm3)
      benchmark: density
    - label: Refractive index, calculated (Ncalc)
      benchmark: refractive_index
    - label: Olivine share in lunar simulants (%)
      benchmark: olivine_modal_abundance
  handling:
    - No supplier safety data sheet for pure forsterite was read in this run. The hazard codes above come from a PubChem record for a mixed olivine.
    - The one dust-related source read describes low levels of free silica in this sand. No dust limit was read.
    - The PubChem GHS record carries an eye-irritation code (H319), so eye protection is a sensible precaution. The wording of P280 was not read in this run.
  good_for:
    - 'Ground-test simulant work: NASA''s JSC-1A page and CLASS''s LMS-1 page both name olivine as a phase, at 9.0% and 11.1 wt.%.'
    - A reference silicate with a printed formula, space group and oxide split (57.29% MgO and 42.71% SiO2 in theory).
  watch_out:
    - The 9.0% and 11.1 wt.% figures describe olivine as one phase of a whole simulant. They are not properties of pure forsterite.
    - WebMineral's printed refractive index ranges are wide, for example 1.636 to 1.73 for index a.
    - PubChem's hazard record is for a mixed magnesium-iron olivine (formula Fe2Mg8O20Si5), not for pure forsterite.
  verdict: Forsterite is well described as a mineral in the sources read, but this profile has no flight, space-environment or processing data for it. Its role here is as a named phase in lunar simulants and as a magnesium-bearing silicate, not as a proven engineering material.