spore: profile
id: bp-1-lunar-simulant
spore_version: 0.2
family: regolith
name: BP-1 Black Point lunar mare simulant
abbreviation: BP-1
role: Physical stand-in for lunar mare soil in excavation and surface mobility tests
category: regolith
type: lunar-simulants
summary: |
  BP-1 Black Point is a lunar mare simulant made from crushed basalt waste. It came from a road-metal quarry on the Black Point lava flow in northern Arizona, and was discovered during a Desert RATS analog test. ARES prints a bulk density of 1.5 to 1.6 g/cm3 and a specific gravity of 2.81 g/cm3, with particles from 1 to 10,000 µm. The NASA users guide says its pebbles and cobbles make it a good physical simulant for excavation and surface mobility work. Its basalt is alkaline and plagioclase-rich, so it does not copy lunar mare chemistry.
best_for: Excavation, flow, drilling and rover mobility tests that need angular basalt rubble with a broad particle size range, pebbles and cobbles included
weakest_at: 'Chemistry: alkaline and plagioclase-rich, with secondary halite, bassanite, calcite and quartz, and a crystalline silica content that needs controls'
identity:
  formula: Crushed basalt rock powder, not one compound. Its chemistry is given as oxides (SiO2, Al2O3, CaO, MgO, Fe2O3, Na2O), mainly labradorite plagioclase and augite pyroxene.
  source: stoeser-2010
  where: Introduction (feedstock paragraph), Table 3 (XRF analyses, Bag All column) and Table 4 (XRD of bulk BP-1)
tags:
  environments: []
  stresses: []
  applications:
    - rovers-and-surface-systems
    - mechanisms
    - structures
    - habitats-and-suits
    - in-space-manufacturing
properties:
  - benchmark: bulk_density
    label: Bulk density
    value: 1.5
    value_high: 1.6
    bound: range
    unit: g/cm3
    scope: material
    conditions:
      state: bulk; compaction and moisture not stated on the page
      attribution: Rahmatian and Metzger 2010, as cited on the ARES page
    method: Range printed on the ARES BP-1 page in the Geomechanical and Physical Properties section, Density table, Bulk row
    status: ground
    source: ares-bp1
    where: Geomechanical and Physical Properties, Density table, Bulk row
  - benchmark: specific_gravity
    label: Specific gravity
    value: 2.81
    unit: g/cm3
    scope: material
    conditions:
      state: as printed in the ARES table header; the page cites Suescun-Florez et al. 2015
    method: Value printed on the ARES BP-1 page (Geomechanical Properties table), attributed there to Suescun-Florez et al. 2015
    status: ground
    source: ares-bp1
    where: Geomechanical Properties table, Specific Gravity column
  - benchmark: void_ratio
    label: Void ratio
    value: 0.49
    value_high: 0.965
    bound: range
    unit: '-'
    scope: material
    conditions:
      state: range as printed; the page attributes it to Suescun-Florez et al. 2015
    method: Range printed on the ARES BP-1 page (Geomechanical Properties table)
    status: ground
    source: ares-bp1
    where: Geomechanical Properties table, Void Ratio column
  - benchmark: relative_max_density
    label: Relative maximum density
    value: 1.86
    unit: g/cm3
    scope: material
    conditions:
      basis: rho(max) as printed in the users guide, averaged reference Suescun-Flores et al. 2015
    method: Value printed in the users guide density table for BP-1 (rho max column)
    status: ground
    source: nasa-guide-2024
    where: Table 16 (Lunar simulant density values), BP-1 row, rho(max) column
  - benchmark: relative_min_density
    label: Relative minimum density
    value: 1.43
    unit: g/cm3
    scope: material
    conditions:
      basis: rho(min) as printed in the users guide, reference Suescun-Flores et al. 2015
    method: Value printed in the users guide density table for BP-1 (rho min column)
    status: ground
    source: nasa-guide-2024
    where: Table 16 (Lunar simulant density values), BP-1 row, rho(min) column
  - benchmark: hardness
    label: Hardness (Mohs scale)
    value: 4
    value_high: 5
    bound: range
    unit: Mohs scale
    scope: material
    conditions:
      state: as printed on the ARES page
    method: Range printed on the ARES BP-1 page (Geomechanical Properties table, Hardness column)
    status: ground
    source: ares-bp1
    where: Geomechanical Properties table, Hardness (Mohs scale) column
  - benchmark: cohesion
    label: Triaxial cohesion, range
    value: 0
    value_high: 2
    bound: range
    unit: kPa
    scope: material
    conditions:
      test: triaxial shear strength, as cited on the ARES page to Suescun-Florez et al. 2015
      note: the page does not give test details
    method: 'Range printed on the ARES BP-1 page (Triaxial: Shear Strength, Cohesion column)'
    status: ground
    source: ares-bp1
    where: Geomechanical Properties table, Triaxial Shear Strength, Cohesion (kPa) column
  - benchmark: cohesion
    label: Cohesion, average (shear strength reference)
    value: 1
    value_high: 2
    bound: range
    unit: kPa
    scope: material
    conditions:
      basis: average and range as printed in the users guide; reference Suescun-Flores et al. 2015
      region: Low-Ti mare
    method: Average printed in the users guide shear strength table, BP-1 row (C avg column, range 0-2.0)
    status: ground
    source: nasa-guide-2024
    where: Table 19 (Lunar simulant shear strength values), BP-1 row, C (kPa) columns
  - benchmark: friction_angle
    label: Friction angle, range
    value: 39
    value_high: 51
    bound: range
    unit: °
    scope: material
    conditions:
      test: triaxial shear strength, as cited on the ARES page to Suescun-Florez et al. 2015
    method: 'Range printed on the ARES BP-1 page (Triaxial: Shear Strength, Friction Angle column)'
    status: ground
    source: ares-bp1
    where: Geomechanical Properties table, Triaxial Shear Strength, Friction Angle (°) column
  - benchmark: friction_angle
    label: Friction angle, average
    value: 45
    value_high: 51
    bound: range
    unit: °
    scope: material
    conditions:
      basis: average and range as printed in the users guide; reference Suescun-Flores et al. 2015
      region: Low-Ti mare
    method: Average printed in the users guide shear strength table, BP-1 row (phi avg column, range 39.0-51.0)
    status: ground
    source: nasa-guide-2024
    where: Table 19 (Lunar simulant shear strength values), BP-1 row, phi (degrees) columns
  - benchmark: particle_size_range
    label: Particle size range
    value: 1
    value_high: 10000
    bound: range
    unit: µm
    scope: material
    conditions:
      basis: range printed on the ARES page, General Properties table
    method: Range printed on the ARES BP-1 page (General Properties, Particle Size Range column, printed as 1 - 10,000)
    status: ground
    source: ares-bp1
    where: General Properties table, Particle Size Range (µm) column
  - benchmark: mean_particle_size
    label: Mean particle size
    value: 100
    unit: µm
    scope: material
    conditions:
      basis: mean printed on the ARES page, General Properties table
    method: Value printed on the ARES BP-1 page (General Properties, Mean Particle Size column)
    status: ground
    source: ares-bp1
    where: General Properties table, Mean Particle Size (µm) column
  - benchmark: particle_size_q25
    label: Particle size, 25th quartile (Q25)
    value: 36.4
    unit: µm
    scope: material
    conditions:
      basis: average Q25 of % passing grains, as printed in the users guide; reference Clark 2021 (JSC-ARES)
      region: Low-Ti mare
    method: Value printed in the users guide particle size table, BP-1 row
    status: ground
    source: nasa-guide-2024
    where: Table 10 (Lunar regolith simulant PSD), BP-1 row, Q25 column
  - benchmark: median_particle_size_d50
    label: Particle size, median (Q50)
    value: 88.4
    unit: µm
    scope: material
    conditions:
      basis: average Q50 of % passing grains, as printed in the users guide; reference Clark 2021 (JSC-ARES)
      region: Low-Ti mare
    method: Value printed in the users guide particle size table, BP-1 row
    status: ground
    source: nasa-guide-2024
    where: Table 10 (Lunar regolith simulant PSD), BP-1 row, Q50 column
  - benchmark: particle_size_q75
    label: Particle size, 75th quartile (Q75)
    value: 205
    unit: µm
    scope: material
    conditions:
      basis: average Q75 of % passing grains, as printed in the users guide; reference Clark 2021 (JSC-ARES)
      region: Low-Ti mare
    method: Value printed in the users guide particle size table, BP-1 row
    status: ground
    source: nasa-guide-2024
    where: Table 10 (Lunar regolith simulant PSD), BP-1 row, Q75 column
  - benchmark: aspect_ratio
    label: Particle aspect ratio (image analysis)
    value: 0.67
    unit: '-'
    scope: material
    conditions:
      basis: bulk value from SDL 2022 (JSC-ARES) particle images, as printed in the users guide
    method: Value printed in the users guide particle geometry table, BP-1 row
    status: ground
    source: nasa-guide-2024
    where: Table 13 (Lunar regolith simulant particle geometry), BP-1 row, AR column
  - benchmark: sqrt_form_factor
    label: Root form factor (image analysis)
    value: 0.93
    unit: '-'
    scope: material
    conditions:
      basis: bulk value from SDL 2022 (JSC-ARES) particle images, as printed in the users guide
    method: Value printed in the users guide particle geometry table, BP-1 row
    status: ground
    source: nasa-guide-2024
    where: Table 13 (Lunar regolith simulant particle geometry), BP-1 row, root FF column
  - benchmark: sio2
    label: Silicon dioxide (average of 5 bags)
    value: 44
    unit: wt%
    scope: material
    conditions:
      basis: whole-rock XRF, average of five 1-ton lots (Bag All)
      sample: BP-1 bulk
    method: Value printed in the Stoeser et al. 2010 XRF table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 3 (XRF analyses of BP-1 splits), SiO2 row, Bag All column
  - benchmark: al2o3
    label: Aluminium oxide (average of 5 bags)
    value: 17
    unit: wt%
    scope: material
    conditions:
      basis: whole-rock XRF, average of five lots (Bag All)
    method: Value printed in the Stoeser et al. 2010 XRF table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 3 (XRF analyses of BP-1 splits), Al2O3 row, Bag All column
  - benchmark: cao
    label: Calcium oxide (average of 5 bags)
    value: 14
    unit: wt%
    scope: material
    conditions:
      basis: whole-rock XRF, average of five lots (Bag All); the authors link high CaO to secondary minerals
    method: Value printed in the Stoeser et al. 2010 XRF table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 3 (XRF analyses of BP-1 splits), CaO row, Bag All column
  - benchmark: mgo
    label: Magnesium oxide (average of 5 bags)
    value: 8
    unit: wt%
    scope: material
    conditions:
      basis: whole-rock XRF, average of five lots (Bag All)
    method: Value printed in the Stoeser et al. 2010 XRF table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 3 (XRF analyses of BP-1 splits), MgO row, Bag All column
  - benchmark: fe2o3
    label: Iron(III) oxide (average of 5 bags)
    value: 11
    unit: wt%
    scope: material
    conditions:
      basis: whole-rock XRF, average of five lots (Bag All)
    method: Value printed in the Stoeser et al. 2010 XRF table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 3 (XRF analyses of BP-1 splits), Fe2O3 row, Bag All column
  - benchmark: na2o
    label: Sodium oxide (average of 5 bags)
    value: 3
    unit: wt%
    scope: material
    conditions:
      basis: whole-rock XRF, average of five lots (Bag All)
    method: Value printed in the Stoeser et al. 2010 XRF table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 3 (XRF analyses of BP-1 splits), Na2O row, Bag All column
  - benchmark: k2o
    label: Potassium oxide (average of 5 bags)
    value: 0
    unit: wt%
    scope: material
    conditions:
      basis: whole-rock XRF, average of five lots (Bag All). The USGS sample W172158 in Table 1 gives 1.1 wt%, a conflict recorded in gaps
    method: Value printed in the Stoeser et al. 2010 XRF table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 3 (XRF analyses of BP-1 splits), K2O row, Bag All column
  - benchmark: labradorite
    label: Labradorite (plagioclase), bulk XRD
    value: 60.7
    unit: wt%
    scope: material
    conditions:
      basis: preliminary XRD of a bulk simulant sample, labelled preliminary and unverified by the authors
    method: Value printed in the Stoeser et al. 2010 XRD table for bulk BP-1; ARES prints the same value
    status: ground
    source: stoeser-2010
    where: Table 4 (XRD of bulk BP-1 simulant), Labradorite row
  - benchmark: augite
    label: Augite (pyroxene), bulk XRD
    value: 23.7
    unit: wt%
    scope: material
    conditions:
      basis: preliminary XRD of a bulk simulant sample, labelled preliminary and unverified by the authors
    method: Value printed in the Stoeser et al. 2010 XRD table for bulk BP-1; ARES prints the same value
    status: ground
    source: stoeser-2010
    where: Table 4 (XRD of bulk BP-1 simulant), Augite row
  - benchmark: olivine
    label: Olivine, bulk XRD
    value: 6.2
    unit: wt%
    scope: material
    conditions:
      basis: preliminary XRD of a bulk simulant sample, labelled preliminary and unverified by the authors
    method: Value printed in the Stoeser et al. 2010 XRD table for bulk BP-1; ARES prints the same value
    status: ground
    source: stoeser-2010
    where: Table 4 (XRD of bulk BP-1 simulant), Olivine row
  - benchmark: halite
    label: Halite (NaCl), range printed on ARES
    value: 1
    value_high: 5
    bound: range
    unit: wt%
    scope: material
    conditions:
      basis: range given in the ARES use notes; Stoeser et al. 2010 Table 5 gives 1 to 5 wt% across the five bags
    method: Range printed on the ARES BP-1 page (Recommendation section, Drilling and Human Health rows)
    status: ground
    source: ares-bp1
    where: Recommendation section, Drilling row (halite 1-5 wt.%)
  - benchmark: bassanite
    label: Bassanite (CaSO4 0.5 H2O), range printed on ARES
    value: 1
    value_high: 3
    bound: range
    unit: wt%
    scope: material
    conditions:
      basis: range given in the ARES use notes. Stoeser et al. 2010 Table 5 shows bag 4 at 4 wt%, outside this range; recorded in gaps
    method: Range printed on the ARES BP-1 page (Recommendation section, Drilling row)
    status: ground
    source: ares-bp1
    where: Recommendation section, Drilling row (bassanite 1-3 wt.%)
  - benchmark: halite
    label: Halite, sieved <10 µm splits, all bags
    value: 1
    unit: wt%
    scope: material
    conditions:
      basis: XRD of <10-µm splits, Bag All column; the salt was confirmed by washing with distilled water
    method: Value printed in the Stoeser et al. 2010 XRD summary table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 5 (XRD summary table for <10-µm splits of BP-1), Halite row, Bag All
  - benchmark: bassanite
    label: Bassanite, sieved <10 µm splits, all bags
    value: 2
    unit: wt%
    scope: material
    conditions:
      basis: XRD of <10-µm splits, Bag All column; individual bags range 0 to 4 wt%
    method: Value printed in the Stoeser et al. 2010 XRD summary table, Bag All column
    status: ground
    source: stoeser-2010
    where: Table 5 (XRD summary table for <10-µm splits of BP-1), Bassanite row, Bag All
  - benchmark: cristobalite
    label: Cristobalite, NIOSH 7500 XRD of 10 bags
    value: 0.57
    value_high: 2.9
    bound: range
    unit: wt%
    scope: material
    conditions:
      basis: 10 one-ton bags sampled by the Kennedy Space Center industrial hygiene office, NIOSH 7500 method by XRD; the authors call these values highly improbable for this rock
    method: Range printed in the Stoeser et al. 2010 health section, quoting the IHO report
    status: ground
    source: stoeser-2010
    where: Section 5 (Health), second paragraph
  - benchmark: quartz
    label: Quartz, NIOSH 7500 XRD of 10 bags (upper value)
    value: 2.3
    bound: upper
    unit: wt%
    scope: material
    conditions:
      basis: up to this value across 10 one-ton bags, NIOSH 7500 method by XRD; the authors say the quartz in the feedstock is secondary
    method: Value printed in the Stoeser et al. 2010 health section, quoting the IHO report
    status: ground
    source: stoeser-2010
    where: Section 5 (Health), second paragraph
  - benchmark: crystalline_silica_total
    label: Total crystalline silica, 2010 analysis
    value: 1.89
    unit: wt%
    scope: material
    conditions:
      basis: analysis symbol printed as ¤ (2010) in the users guide; the symbol key is not in the text read
    method: Value printed in the users guide crystalline silica summary, BP-1 row
    status: ground
    note: Disagrees with the 2022 and 2023 rows (0.36 and 0.52 wt%). Both values are printed; neither is preferred.
    source: nasa-guide-2024
    where: Table 25 (Summary of total percent crystalline and respirable silica), BP-1 row, 2010 analysis
  - benchmark: crystalline_silica_total
    label: Total crystalline silica, 2022 analysis
    value: 0.36
    unit: wt%
    scope: material
    conditions:
      basis: analysis symbol printed as ‡ (2022) in the users guide; the symbol key is not in the text read
    method: Value printed in the users guide crystalline silica summary, BP-1 row
    status: ground
    source: nasa-guide-2024
    where: Table 25 (Summary of total percent crystalline and respirable silica), BP-1 row, 2022 analysis
  - benchmark: crystalline_silica_total
    label: Total crystalline silica, 2023 analysis
    value: 0.52
    unit: wt%
    scope: material
    conditions:
      basis: analysis symbol printed as § (2023) in the users guide; the symbol key is not in the text read
    method: Value printed in the users guide crystalline silica summary, BP-1 row
    status: ground
    source: nasa-guide-2024
    where: Table 25 (Summary of total percent crystalline and respirable silica), BP-1 row, 2023 analysis
  - benchmark: respirable_fraction_under_10um
    label: Percent passing under 10 µm, respirable fraction
    value: 11.5
    unit: '%'
    scope: material
    conditions:
      basis: 2023 analysis as printed in the users guide
    method: Value printed in the users guide crystalline silica summary, BP-1 2023 row
    status: ground
    source: nasa-guide-2024
    where: Table 25 (Summary of total percent crystalline and respirable silica), BP-1 2023 row, percent passing under 10 µm
  - benchmark: respirable_crystalline_silica
    label: Respirable crystalline silica, 2023 analysis
    value: 0.06
    unit: wt%
    scope: material
    conditions:
      basis: total respirable crystalline silica, 2023 analysis as printed in the users guide
    method: Value printed in the users guide crystalline silica summary, BP-1 2023 row
    status: ground
    source: nasa-guide-2024
    where: Table 25 (Summary of total percent crystalline and respirable silica), BP-1 2023 row, total respirable crystalline silica column
  - benchmark: aspect_ratio
    label: Particle aspect ratio, average (Dotson et al. 2024)
    value: 0.654
    unit: '-'
    scope: material
    conditions:
      basis: average aspect ratio (a) from image analysis of particles on an optical microscope, CILAS-1190 with 40x objective, per Dotson et al. 2024 section 2.2
    method: Value printed in Table 2 (Measured particle shapes), BP-1 row, a column
    status: ground
    source: dotson-2024
    where: Table 2 (Measured particle shapes), BP-1 row, a column
  - benchmark: sphericity
    label: Particle sphericity (Dotson et al. 2024)
    value: 0.528
    unit: '-'
    scope: material
    conditions:
      basis: image analysis as for aspect ratio, per Dotson et al. 2024 section 2.2
    method: Value printed in Table 2 (Measured particle shapes), BP-1 row, s column
    status: ground
    source: dotson-2024
    where: Table 2 (Measured particle shapes), BP-1 row, s column
  - benchmark: equivalent_circular_diameter
    label: Equivalent circular diameter, average (xECD)
    value: 27.56
    unit: µm
    scope: material
    conditions:
      basis: image analysis as for aspect ratio, per Dotson et al. 2024 section 2.2
    method: Value printed in Table 2 (Measured particle shapes), BP-1 row, xECD column
    status: ground
    source: dotson-2024
    where: Table 2 (Measured particle shapes), BP-1 row, xECD column
  - benchmark: median_particle_size_d50
    label: Particle size D50 (Dotson et al. 2024)
    value: 228.91
    unit: µm
    scope: material
    conditions:
      basis: D50 from the particle size distribution printed in Table 3; differs from the users guide Q50 of 88.4 µm, and both are recorded
    method: Value printed in Table 3 (Particle Size Distributions), BP-1 row, D50 column
    status: ground
    source: dotson-2024
    where: Table 3 (Particle Size Distributions), BP-1 row, D50 column
corrosion:
  - environment: Hydrated mixture with ice (ice-regolith tests)
    headline: Halite and bassanite may change chemical reactivity when BP-1 is mixed with ice.
    effect: ARES rates BP-1 potentially suitable for drilling when hydrated. It says the presence of halite (1-5 wt.%) and bassanite (1-3 wt.%) may affect studies with ice regolith mix because of changes in chemical reactivity.
    rating: unknown
    conditions:
      basis: ARES use note; no test on BP-1 is cited
    source: ares-bp1
    where: Recommendation section, Drilling row (potentially suitable, hydrated)
  - environment: Oxygen extraction and metal production (volatiles and reactions with hardware)
    headline: Chlorine from halite and sulfur from bassanite can contaminate oxygen extraction products and react with hardware.
    effect: ARES says that Cl from halite and S from bassanite raise potential problems for volatiles processing and oxygen extraction, including reactivity, contamination of products and reactions with hardware. It says calcite may cause unwanted reactions in metal production. ARES rates BP-1 potentially suitable with caution for both.
    rating: unknown
    conditions:
      basis: ARES recommendation text; no BP-1 extraction test is cited
    source: ares-bp1
    where: Recommendation section, Oxygen Production and Metal Production rows
  - environment: Natural weathering of the source basalt
    headline: Calcite and quartz in BP-1 are secondary minerals made by weathering or alteration of the basalt, not primary minerals.
    effect: Stoeser et al. (2010) say calcite and quartz are not primary minerals and derive from weathering or alteration of the original basalt. Calcite ranges from 9 wt% to nil between bags, and olivine varies between bags, which the authors call probably real. Total secondary minerals in the under-10 mm splits are printed as 9 to 24 per cent.
    rating: unknown
    conditions:
      basis: XRD of bulk and sieved splits; the bulk XRD is labelled preliminary and unverified by the authors
    source: stoeser-2010
    where: Section 3 (Mineralogy), Table 5 and text below it
risks:
  hazards:
    - text: The users guide prints total crystalline silica for BP-1 as 1.89 wt% in a 2010 row, 0.36 wt% in a 2022 row and 0.52 wt% in a 2023 row. The 2023 row also prints a respirable fraction (under 10 µm) of 11.5 per cent and total respirable crystalline silica of 0.06 wt%. The three totals disagree, and the analysis symbols are not defined in the text read.
      ghs: []
      source: nasa-guide-2024
      where: Table 25, BP-1 rows
    - text: Stoeser et al. (2010) quote an industrial hygiene evaluation of ten one-ton bags of BP-1. NIOSH 7500 XRD found 0.57 to 2.9 wt% cristobalite and up to 2.3 wt% quartz in every bag. The authors say the cristobalite values are highly improbable for this source rock, because cristobalite forms only at very high temperature.
      ghs: []
      source: stoeser-2010
      where: Section 5 (Health), second and third paragraphs
    - text: In a November 2023 test, moving BP-1 from bulk containers over 71 minutes gave a crystalline silica 8-hour TWA result below 5.22 µg/m3 and a respirable PNOR 8-hour TWA of 0.09 mg/m3. The guide gives these as Simulant Development Lab results.
      ghs: []
      source: nasa-guide-2024
      where: Table 26 (Silica and PNOR monitoring in the Simulant Development Lab), row Transfer of BP-1 from bulk containers, November 2023
    - text: 'The users guide lists the OSHA limits used at NASA: crystalline silica at 50 µg/m3 as an 8-hour TWA, and respirable particulates not otherwise regulated (PNOR) at 5 mg/m3 as an 8-hour TWA.'
      ghs: []
      source: nasa-guide-2024
      where: OSHA Permissible Exposure Limit list, immediately before Section 5.9
    - text: Stoeser et al. (2010) say that the abundance of fine particles is certainly a concern for health applications should they become airborne.
      ghs: []
      source: stoeser-2010
      where: Section 4 (Particle size), closing paragraph
    - text: 'The file that the ARES BP-1 page links as BP-1_SDS.pdf is a Rinker Materials safety data sheet for generic aggregate products (MSDS #0001, revision 2, effective August 1, 2001). It does not name BP-1, so its statements are general. It says that respirable crystalline silica can cause silicosis, is a cancer hazard when inhaled, and that aggregates may contain more than 0.1% crystalline silica.'
      ghs: []
      source: rinker-msds
      where: Sections II and VI
    - text: PubChem silica record (CID 24261) lists cristobalite notifications to ECHA and NITE-CMC with H350 May cause cancer and H372 Causes damage to organs through prolonged or repeated exposure, signal word Danger, health hazard pictogram. The aggregated top-level silica entry reads Not Classified. These statements are for cristobalite, which Stoeser et al. report in BP-1 by NIOSH 7500 XRD. No source read gives a GHS classification for the BP-1 material itself.
      ghs:
        - H350
        - H372
      source: pubchem-silica
      where: GHS Classification, Cristobalite (EC 238-455-4) and NITE-CMC Cristobalite (FY2015) notifications
    - text: The 2019 University of Cape Town dissertation on sintered BP-1 says that human exposure to BP-1 can affect the respiratory organs and cause acute silicosis, and that BP-1 is very reactive with acid and with oxidising agents. It gives no exposure measurement and no test reference for these statements.
      ghs: []
      source: uct-thesis-2019
      where: Chapter One (Introduction), handling paragraphs
    - text: OSHA annotated Table Z-3 gives respirable quartz as 250 (%SiO2+5) mppcf and 10 mg/m3 (%SiO2+2), formulas in percent SiO2 rather than a fixed number. Footnote (l) says these Z-3 entries apply only where the respirable crystalline silica standard 1910.1053 is stayed or otherwise not in effect. The 50 µg/m3 limit in the users guide is a separate entry and is kept as printed there.
      ghs: []
      source: osha-z3
      where: Annotated Table Z-3 Mineral Dusts, Silica crystalline, Quartz (Respirable) row and footnote (l)
  failure_risks:
    - mode: Over-compaction of the simulant
      trigger: Compacting BP-1 in excavation and soil-bin tests
      consequence: ARES says care must be taken to avoid over compaction compared with lunar regolith, so a compacted bed can behave unlike the Moon.
      source: ares-bp1
      where: Recommendation section, Excavation / Flow row
    - mode: Altered dust behavior from weathered minerals
      trigger: Use in human health or dust studies
      consequence: ARES says the presence of weathered minerals may alter dust behavior with other materials when compared with lunar fines. It prints secondary minerals as 9-24% in samples under 10 µm.
      source: ares-bp1
      where: Recommendation section, Human Health Studies row
    - mode: Shipment-to-shipment and bag-to-bag mineral variation
      trigger: Using a new shipment or sample without checking
      consequence: ARES says plagioclase and olivine amounts vary greatly between whole shipments and samples of fines, and should be verified before use. Stoeser et al. report calcite from 9 wt% to nil between bags.
      source: ares-bp1
      where: Recommendation section, Oxygen Production row
  side_effects:
    - text: ARES says Cl from halite and S from bassanite may cause problems for volatiles processing and oxygen extraction, including contamination of products and reactions with hardware.
      affects: Oxygen extraction products and process hardware
      source: ares-bp1
      where: Recommendation section, Oxygen Production row
  handling:
    - text: The users guide says the JSC Simulant Development Lab maintains a safety data sheet for every simulant. Request the BP-1 sheet from that lab, because no BP-1-specific sheet was read in this run.
      source: nasa-guide-2024
      where: Section 5.9.1 (Johnson Space Center and SDL requirements)
    - text: The Kennedy Space Center industrial hygiene office recommended, for the BP-1 sandbox trial, that non-essential people be kept out of the area, that a decontamination area with a HEPA vacuum be used for equipment, and that hand-wash and eye-wash facilities be provided.
      source: stoeser-2010
      where: Section 5 (Health), recommendations paragraph
    - text: The generic aggregate sheet advises cleaning up spilled dust with vacuuming, wet mopping or moistening with water, so that dust does not go airborne. This is general aggregate advice, not a BP-1 instruction.
      source: rinker-msds
      where: Section VII (Steps to be taken in case material is released or spilled)
  mitigations:
    - text: The users guide says exposure monitoring is the only method to determine occupational exposure to crystalline silica. It reports that all JSC exposures to date were below the OSHA PEL and Action Level for crystalline silica. This covers all simulant tasks at JSC, not BP-1 alone.
      source: nasa-guide-2024
      where: Section 5.8 (Workplace Monitoring)
    - text: The industrial hygiene office recommended personal protective equipment and controls until exposure measurements could be made. For test judges, it said respiratory protection must comply with OSHA Respiratory Standard 1910.134, including medical certification, fit testing and training.
      source: stoeser-2010
      where: Section 5 (Health), recommendations and quoted report
uses:
  - application: rovers-and-surface-systems
    device: Excavation and flow tests
    example: ARES rates BP-1 recommended for excavation and flow. Its particle size distribution and angular, elongated grains produce a high angle of repose in large piles.
    source: ares-bp1
    where: Recommendation section, Excavation / Flow row; Geomechanical Properties table, Angle of Repose column
  - application: rovers-and-surface-systems
    device: Excavation, construction and surface mobility projects
    example: The users guide says BP-1's pebble- and cobble-sized rock mixed with finer particles makes it a good physical simulant for excavation, construction and surface mobility technology projects.
    source: nasa-guide-2024
    where: Section 3.4 (Lunar Regolith Simulants for NASA's Constellation Program), BP-1 paragraph
  - application: structures
    device: Construction materials tests
    example: ARES rates BP-1 potentially suitable for construction, citing adequate grain size, shape, distribution and basaltic mineralogy, and notes that calcite may affect reactivity with other components.
    source: ares-bp1
    where: Recommendation section, Construction row
  - application: mechanisms
    device: Dry drilling and abrasion tests
    example: ARES rates BP-1 recommended for dry drilling and for abrasion and wear, because its angular elongated grains and particle size distribution make an abrasive material with adequate mineralogy.
    source: ares-bp1
    where: Recommendation section, Drilling (Dry) and Abrasion / Wear rows
  - application: habitats-and-suits
    device: Dust mitigation for habitats (test material)
    example: ARES rates BP-1 potentially suitable for dust mitigation in habitats, because it has adequate fines, particle size distribution and grain shapes, but weathered minerals may alter its dust behavior compared with lunar fines.
    source: ares-bp1
    where: Recommendation section, Human Health Studies row
supply:
  - subject: BP-1 quarry waste
    abundance: Not stated in any source read. ARES gives no tonnage or producer share.
    producers: []
    origin: BP-1 is silt-sized washing waste from an aggregate (road metal) quarry on the northern margin of the Black Point basalt flow, towards the west end. The flow is about 60 miles (100 km) NNE of Flagstaff, AZ, in the San Francisco Volcanic Field of northern Arizona. ARES says it was collected from quarry washing waste and was not processed or modified after collection.
    status: Stoeser et al. say the quarry wash water probably comes from a saline aquifer. Because the water is reused, dissolved salts concentrate and precipitate halite and bassanite.
    source: stoeser-2010
    where: Introduction (feedstock paragraph); Section 3 (Mineralogy), text on halite and bassanite
  - subject: BP-1 holder and sampling
    abundance: Not stated.
    producers: []
    origin: The users guide lists BP-1 as a Low-Ti mare simulant with its source as NASA KSC. Stoeser et al. say that samples from five different 1-ton lots were taken for analysis.
    source: nasa-guide-2024
    where: Table 2 (List of simulants assessed with corresponding lunar region and source), BP-1 row
media: []
documents:
  - title: NASA ARES, BP-1 Black Point lunar mare simulant project page
    type: database
    url: https://ares.jsc.nasa.gov/projects/simulants/bp-1.html
  - title: NASA/TM-20240011783, Lunar Regolith Simulant User's Guide, Revision A
    type: report
    url: https://ntrs.nasa.gov/api/citations/20240011783/downloads/Lunar_Regolith_Simulant_Users_Guide_Rev_A_28OCT.pdf
    year: 2024
  - title: NASA/TM-2010-216444, Preliminary Geological Findings on the BP-1 Simulant (Stoeser, Rickman and Wilson)
    type: report
    url: https://ntrs.nasa.gov/api/citations/20100036344/downloads/20100036344.pdf
    year: 2010
  - title: Material Safety Data Sheet for Aggregate Products, Rinker Materials (linked from the ARES BP-1 page as BP-1_SDS.pdf; generic, not BP-1 specific)
    type: sds
    url: https://ares.jsc.nasa.gov/projects/simulants/_resources/BP-1_SDS.pdf
    year: 2001
  - title: Dotson et al. 2024, Cohesion and Shear Strength of Compacted Lunar and Martian Regolith Simulants (arXiv 2403.11029)
    type: paper
    url: https://arxiv.org/pdf/2403.11029
    year: 2024
  - title: Ogunyinka 2019, Investigation of Material Properties of Sintered Black Point-1 Lunar Regolith Simulant (University of Cape Town MPhil dissertation)
    type: report
    url: https://open.uct.ac.za/server/api/core/bitstreams/ead778a3-7849-4fc1-9289-f09448b8c30b/content
    year: 2019
  - title: PubChem compound record CID 24261 (Silica), GHS Classification
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/24261/JSON?heading=GHS+Classification
  - title: OSHA Annotated Table Z-3, Mineral Dusts
    type: standard
    url: https://www.osha.gov/annotated-pels/table-z-3
gaps:
  - No BP-1-specific safety data sheet was found. The file the ARES page links as BP-1_SDS.pdf is a generic aggregate sheet from Rinker Materials, so the BP-1 hazard entries rest on the users guide and on Stoeser et al. 2010.
  - 'Angle of repose: ARES gives only a qualitative description (high angle of repose in large piles), with no number.'
  - 'Grain density and porosity: not printed. ARES gives specific gravity and void ratio only.'
  - 'Uniaxial Young''s modulus and uniaxial tensile strength: printed as dashes on the ARES page.'
  - 'Agglutinate and glass content: not printed by ARES or Stoeser et al. The users guide table for BP-1 was garbled in text extraction, so no value is recorded.'
  - 'Thermophysical properties: ARES says they are not yet characterized, and the simulant development lab analytical results are printed as Pending analyses.'
  - 'Source conflicts, recorded side by side and not resolved: K2O is 0 wt% in the five-bag average (Stoeser Table 3) but 1.1 wt% in USGS sample W172158 (Stoeser Table 1). Bassanite is 1 to 3 wt% on the ARES page but 4 wt% in bag 4 of Stoeser Table 5. Total secondary minerals are printed as 9 to 24 per cent in Stoeser''s text, while Table 5 gives 8 to 24 across the bags. Quartz is 1 to 2 wt% on ARES, 1.7 wt% in the bulk XRD and 3 wt% in the sieved splits. Total crystalline silica is 1.89, 0.36 and 0.52 wt% in three users guide rows.'
  - Halite is 1 to 5 wt% on ARES and 1 wt% in the Bag All sieved split of Stoeser Table 5. Both are recorded.
  - The users guide defines no key for the analysis symbols (¤, ‡, §) in Table 25. The source of each total silica value is therefore not confirmed.
  - 'Suescun-Florez et al. 2015 and Rahmatian and Metzger 2010 are cited for several values. Their papers were not opened: the ASCE page for Suescun-Florez returned a bot-check page. Values from those studies are attributed through the ARES and users guide pages that print them.'
  - 'Supplier and production shares: BP-1 is not commercially made and no supply shares apply. Critical-mineral lists (USGS, EU) were not checked for this profile.'
  - Corrosion and reactivity ratings are not given by any source, so each is recorded as unknown.
  - 'Lunar-day, lunar-night, vacuum, thermal-cycling and radiation behavior: no source read in this run tests BP-1 under those conditions, so tags.environments and tags.stresses are empty.'
  - The UCF Planetary Simulant Database page linked from ARES (simulantdb.com) returned unrelated content, so its fidelity rating is not used. ARES itself labels BP-1 as basic fidelity under that database's guidelines.
  - 'Property names not in spores/property-canon.yaml: equivalent_circular_diameter, sphericity, bulk_density, specific_gravity, void_ratio, hardness, cohesion, friction_angle, particle_size_range, mean_particle_size, particle_size_q25, particle_size_q75, relative_max_density, relative_min_density, aspect_ratio, sqrt_form_factor, sio2, al2o3, cao, mgo, fe2o3, na2o, k2o, labradorite, augite, olivine, halite, bassanite, cristobalite, quartz, crystalline_silica_total, respirable_fraction_under_10um and respirable_crystalline_silica. Names follow the existing lunar-regolith-simulant profile where one exists.'
  - 'Sources: eight are now opened and cited: the ARES page, the users guide, Stoeser et al. 2010, the linked SDS, Dotson et al. 2024 (arXiv), the Ogunyinka 2019 dissertation, the PubChem silica record and OSHA Table Z-3. Still not reached: Suescun-Florez et al. 2015 (its ASCE page gave no full text here, and a web search returned only the abstract, so no value is taken from it) and the UCF simulant database page.'
  - 'Specific gravity conflict, recorded and not entered: the Ogunyinka 2019 dissertation says "The specific gravity of BP-1 lies within the range of 2.45-2.80", cites Eduardo et al. 2014, and prints no unit. ARES gives 2.81 g/cm3. The range is not entered as a property because no unit is printed.'
  - 'Particle size D50 conflict, both recorded: Dotson et al. 2024 Table 3 prints 228.91 µm, and the users guide Q50 is 88.4 µm. The measurement method behind the Dotson value was not read in this run.'
  - 'Aspect ratio conflict, both recorded: Dotson et al. 2024 Table 2 prints 0.654 for BP-1, and the users guide prints 0.67 for BP-1 (SDL 2022 images).'
sources:
  ares-bp1:
    title: BP-1 Black Point lunar mare simulant, NASA ARES Simulants project page
    id: NASA Exploration Research and Simulation (ARES), JSC simulants project
    url: https://ares.jsc.nasa.gov/projects/simulants/bp-1.html
    kind: web
    license: NASA web page, public information; licence not stated on the page read
  nasa-guide-2024:
    title: Lunar Regolith Simulant User's Guide, Revision A
    id: NASA/TM-20240011783, effective 10/24/2024 (NTRS 20240011783)
    url: https://ntrs.nasa.gov/api/citations/20240011783/downloads/Lunar_Regolith_Simulant_Users_Guide_Rev_A_28OCT.pdf
    year: 2024
    kind: report
    license: NASA public document; licence not stated in the copy read
  stoeser-2010:
    title: Preliminary Geological Findings on the BP-1 Simulant (Stoeser, Rickman and Wilson, NASA technical memorandum)
    id: NASA/TM-2010-216444; NTRS 20100036344; report number M-1293
    url: https://ntrs.nasa.gov/api/citations/20100036344/downloads/20100036344.pdf
    year: 2010
    kind: report
    license: NASA public document; licence not stated in the copy read
  rinker-msds:
    title: 'Material Safety Data Sheet for Aggregate Products, Rinker Materials Corporation (MSDS #0001, revision 2)'
    id: Effective August 1, 2001; linked from the ARES BP-1 page
    url: https://ares.jsc.nasa.gov/projects/simulants/_resources/BP-1_SDS.pdf
    year: 2001
    kind: datasheet
    license: Supplier document, linked not reproduced. Generic aggregate sheet, not specific to BP-1
  dotson-2024:
    title: Cohesion and Shear Strength of Compacted Lunar and Martian Regolith Simulants
    id: arXiv 2403.11029; B. Dotson, D. Sanchez Valencia, C. Millwater, P. Easter, J. Long-Fox, D. Britt and P. Metzger (University of Central Florida)
    url: https://arxiv.org/pdf/2403.11029
    year: 2024
    kind: paper
    license: arXiv preprint; licence not stated in the copy read
  uct-thesis-2019:
    title: Investigation of Material Properties of Sintered Black Point-1 Lunar Regolith Simulant (MPhil dissertation, Adebayo Olutumbi Ogunyinka)
    id: University of Cape Town, SpaceLab, SL19-010M, September 2019
    url: https://open.uct.ac.za/server/api/core/bitstreams/ead778a3-7849-4fc1-9289-f09448b8c30b/content
    year: 2019
    kind: paper
    license: University of Cape Town thesis; the title page limits use to private study or non-commercial research
  pubchem-silica:
    title: PubChem compound record CID 24261 (Silica), Safety and Hazards, GHS Classification
    id: PubChem CID 24261 (Silica); GHS notifications from ECHA and NITE-CMC
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/24261/JSON?heading=GHS+Classification
    kind: database
    license: PubChem data, public
  osha-z3:
    title: OSHA Annotated Table Z-3, Mineral Dusts
    id: OSHA annotated PEL tables, Table Z-3
    url: https://www.osha.gov/annotated-pels/table-z-3
    kind: standard
    license: US government public information
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 42
  unreachable: 2
  caveats: 4
  note: 'Written by an AI assistant on 2026-11-01 and deepened in a second pass the same day. Documents opened: the ARES BP-1 page (raw HTML, compared with a summarising fetch), the NASA/TM-20240011783 users guide (PDF text), NASA/TM-2010-216444 by Stoeser et al. (PDF text), the linked BP-1_SDS.pdf (a generic aggregate sheet), the Dotson et al. 2024 arXiv paper (PDF text), the Ogunyinka 2019 UCT dissertation (PDF text), the PubChem silica GHS record (CID 24261) and the OSHA annotated Table Z-3 page. Unreachable: the Suescun-Florez 2015 paper (ASCE page gave no full text) and the UCF simulant database page (returned unrelated content). The Rahmatian and Metzger 2010 paper was not found.'
story:
  recipe:
    line: BP-1 is not one compound. It is crushed basalt from the Black Point lava flow, made mostly of labradorite plagioclase feldspar and augite pyroxene by weight, with smaller amounts of olivine, magnetite, and secondary halite and bassanite. Its chemistry is given as oxides, not as a formula. ARES says it was not processed or modified after collection from the quarry washing waste.
    parts:
      - name: Labradorite (plagioclase feldspar)
        symbol: '-'
        share: 60.7 wt% in bulk XRD
        role: The main mineral. Stoeser et al. say plagioclase is much more abundant in the whole sample than in the sieved splits.
      - name: Augite (pyroxene)
        symbol: '-'
        share: 23.7 wt% in bulk XRD
        role: The main mafic mineral after plagioclase, from the original basalt.
      - name: Olivine
        symbol: '-'
        share: 6.2 wt% in bulk XRD
        role: Varies between bags of the same material, which the authors call probably real.
      - name: Silicon dioxide (average)
        symbol: SiO2
        share: 44 wt%
        role: Average silica of the five 1-ton lots. Silica in the BP-1 feedstock is mostly secondary, not primary (Stoeser et al.).
  risk_groups:
    - title: For people
      verdict: Dust is the main concern. Crystalline silica was measured…
      lead: No source read here classifies BP-1 as hazardous. It contains crystalline silica in measured amounts and produces fine dust. The BP-1-specific safety data sheet was not found; the file linked from ARES is a generic aggregate sheet.
      points:
        - label: Crystalline silica
          line: The users guide prints total crystalline silica of 1.89 wt% for a 2010 analysis, 0.36 wt% for 2022 and 0.52 wt% for 2023. The 2023 row gives a respirable fraction of 11.5% and respirable crystalline silica of 0.06 wt%. The three totals disagree, and the guide does not define its analysis symbols in the text read.
        - label: Cristobalite and quartz
          line: Stoeser et al. (2010) quote an industrial hygiene evaluation of ten 1-ton bags. NIOSH 7500 XRD found 0.57 to 2.9 wt% cristobalite and up to 2.3 wt% quartz in every bag. The authors call the cristobalite values highly improbable for this source rock.
        - label: Fine particles
          line: Stoeser et al. say the abundance of fine particles is a concern for health if they become airborne.
        - label: Measured exposure
          line: In a November 2023 test, moving BP-1 from bulk containers for 71 minutes gave a crystalline silica 8-hour TWA result below 5.22 µg/m3 and a respirable PNOR 8-hour TWA of 0.09 mg/m3.
        - label: Limits
          line: The users guide lists OSHA limits of 50 µg/m3 for crystalline silica and 5 mg/m3 for respirable PNOR, both as 8-hour TWA values.
    - title: For a rover or test bed
      lead: Chemistry and dust matter for test beds and oxygen work, not only for people.
      points:
        - label: Salts and reactivity
          line: ARES says halite (1 to 5 wt%) and bassanite (1 to 3 wt%) may change chemical reactivity in ice-regolith mixes, and may cause problems for oxygen extraction.
        - label: Batch variation
          line: ARES says plagioclase and olivine vary greatly between shipments, so each shipment should be checked before use.
        - label: Over-compaction
          line: ARES says care must be taken to avoid over compaction compared with lunar regolith.
    - title: Handling and storage
      points:
        - label: Records
          line: The users guide says the JSC Simulant Development Lab keeps a safety data sheet for every simulant. Request the BP-1 sheet from that lab before use.
        - label: Controls
          line: The industrial hygiene office recommended keeping non-essential people out of the area, a decontamination area with a HEPA vacuum for equipment, and hand-wash and eye-wash facilities for the BP-1 sandbox trial.
        - label: Cleanup
          line: The generic aggregate sheet advises vacuuming, wet mopping or moistening with water to avoid airborne dust. This is general aggregate advice, not a BP-1 instruction.
  why: BP-1 is a lunar mare simulant that was not made to copy lunar chemistry. It is crushed basalt waste from a road-metal quarry in northern Arizona, and it was discovered during a Desert RATS analog test. The users guide says it is attractive because it has pebble- and cobble-sized rock mixed with finer particles, which suits excavation, construction and surface mobility work. Stoeser et al. note that its alkali content is high for a lunar basalt, so it is not suited to tests where composition is critical.
  uses:
    - where: Excavation and flow
      line: ARES rates BP-1 recommended for excavation and flow. Its particle size distribution and angular, elongated grains produce a high angle of repose in large piles.
    - where: Surface mobility and construction
      line: The users guide says BP-1's pebbles and cobbles make it a good physical simulant for excavation, construction and surface mobility technology projects. ARES rates it potentially suitable for construction, with a caution about calcite.
    - where: Drilling and abrasion
      line: ARES rates BP-1 recommended for dry drilling and for abrasion and wear, because its angular grains are abrasive and its mineralogy is adequate.
    - where: Dust mitigation for habitats
      line: ARES rates BP-1 potentially suitable for dust mitigation in habitats, but says weathered minerals may alter its dust behavior compared with lunar fines.
  can_do:
    - label: Grain size
      benchmark: particle_size_range
      value: 1 to 10,000 µm
      line: Particle sizes run from 1 to 10,000 µm, with a mean of 100 µm (ARES). Stoeser et al. describe a large share of particles in a narrow range, plus both fine and coarse particles.
    - label: Grain shape
      benchmark: aspect_ratio
      value: '0.67'
      line: ARES describes the particles as irregular and angular. The users guide gives an aspect ratio of 0.67 and a root form factor of 0.93 for BP-1, from SDL 2022 images.
    - label: Density
      benchmark: bulk_density
      value: 1.5 to 1.6 g/cm3
      line: Bulk density is 1.5 to 1.6 g/cm3 (ARES, citing Rahmatian and Metzger 2010). The users guide gives a relative maximum density of 1.86 g/cm3 and a relative minimum of 1.43 g/cm3, both from Suescun-Florez et al. 2015.
    - label: Strength
      benchmark: friction_angle
      value: 39 to 51 degrees
      line: Triaxial cohesion is 0 to 2.0 kPa and friction angle is 39 to 51 degrees (ARES). The users guide gives an average friction angle of 45 degrees for the same reference.
    - label: Silica
      benchmark: crystalline_silica_total
      value: '0.52'
      line: Total crystalline silica is 0.52 wt% in the 2023 analysis and 1.89 wt% in the 2010 analysis, as printed in the users guide. The two are not reconciled.
  compare: BP-1 is a basalt rubble for ground tests, not a copy of lunar mare chemistry. Stoeser et al. say its high alkali content, relative to lunar basalts, may rule it out where composition is critical, but that this has nothing to do with its behavior as a geotechnical material. ARES says its particle size falls within one standard deviation of the lunar regolith range, and that its mechanical behavior in vibratory densification and shear tests is similar to lunar soil. ARES also lists its high plagioclase content, relative to lunar mare basalt, as a con. The table compares BP-1 with the same benchmarks used for other simulants in this collection.
  compare_rows:
    - label: Bulk density
      benchmark: bulk_density
    - label: Specific gravity
      benchmark: specific_gravity
    - label: Friction angle
      benchmark: friction_angle
  handling:
    - Use a dust mask or respirator where dust forms, following the industrial hygiene controls above.
    - Monitor exposure, because the users guide says monitoring is the only way to measure crystalline silica exposure in the workplace.
    - Check each shipment for halite, bassanite and mineral changes before any test that depends on chemistry.
    - Avoid compacting the bed more than lunar regolith would be compacted.
  good_for:
    - Excavation and flow tests, where the angular, broad particle size distribution gives a high angle of repose (ARES).
    - Rover mobility and construction tests that need basalt rubble with pebbles and cobbles (users guide).
  watch_out:
    - 'Crystalline silica: 1.89 wt% in one 2010 analysis and 0.36 to 0.52 wt% in later rows. Cristobalite is 0.57 to 2.9 wt% in the 2010 industrial hygiene data.'
    - 'Salts: halite and bassanite can change reactivity with ice and can affect oxygen extraction.'
    - 'Composition: alkaline and plagioclase-rich, not lunar mare chemistry.'
    - 'Variation: mineral content changes from bag to bag, so check each shipment.'
  verdict: BP-1 is a physical simulant for excavation and surface mobility tests, not a chemistry match for the Moon. Its silica and salt content need controls, and no source read here tests it under vacuum or thermal conditions.