{
  "spore": "profile",
  "id": "gallium",
  "spore_version": "0.2",
  "family": "gallium",
  "name": "Gallium",
  "abbreviation": "Ga",
  "role": "semiconductor feedstock",
  "category": "metals",
  "type": "heavy-metals",
  "summary": "Gallium (Ga) is a metal that melts near room temperature: the Netzsch safety data sheet gives 29.8 °C and the Periodic Table page gives 29.76 °C. The solid has a density of 5.904 g/cm3 at 20 °C (Netzsch). Most primary low-purity gallium is made in China, and the element matters mainly as feedstock for gallium arsenide and gallium nitride chips, LEDs and solar cells.\n",
  "best_for": "Feedstock for gallium arsenide and gallium nitride chips, LEDs and laser diodes, where the metal is converted into compound wafers (USGS)",
  "weakest_at": "Corrosion and handling: liquid gallium attacks aluminium, the metal melts near 29.8 °C, and the toxicology is only partly investigated",
  "identity": {
    "formula": "Ga (elemental gallium, a metal)",
    "cas": "7440-55-3",
    "designations": [],
    "source": "pubchem-gallium",
    "where": "Names and Identifiers, Other Identifiers (CAS)"
  },
  "tags": {
    "environments": [],
    "stresses": [],
    "applications": [
      "electronics-and-chips",
      "optics-and-cameras",
      "solar-arrays"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density of the solid",
      "value": 5.904,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "temperature": "20 °C",
        "state": "solid"
      },
      "method": "Value printed in the SDS physical properties table",
      "status": "ground",
      "source": "sds-netzsch",
      "where": "Section 9 (Physical and chemical properties), row Density at 20°C",
      "source_detail": {
        "title": "NETZSCH safety data sheet, MSDS E Gallium 6.0 (EC 1907/2006 format)",
        "id": "Version 6.0, revision date 02.08.2022",
        "url": "https://analyzing-testing.netzsch.com/_Resources/Persistent/6/b/1/b/6b1b7407656ada04cf7ff8df6636921100b743d0/MSDS%20E%20Gallium%206.0.pdf",
        "year": 2022,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Density of the liquid",
      "value": 6.095,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "state": "liquid",
        "temperature": "not stated on the page"
      },
      "method": "Value printed in the Bulk physical properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Bulk physical properties, row Density (Liquid)",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point (Periodic Table)",
      "value": 29.76,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "pressure": "not stated on the page"
      },
      "method": "Value printed in the Thermal properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Thermal properties, row Melting Point",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point (PubChem)",
      "value": 29.78,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "basis": "PubChem experimental property, value as printed"
      },
      "method": "Value printed in the PubChem experimental properties record",
      "status": "ground",
      "note": "Differs from the Periodic Table value (29.76 °C) in the second decimal place; both are kept.",
      "source": "pubchem-gallium",
      "where": "Experimental Properties, Melting Point",
      "source_detail": {
        "title": "PubChem compound record, Gallium (CID 5360835), JSON view",
        "id": "CID 5360835; CAS 7440-55-3",
        "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/5360835/JSON",
        "kind": "database",
        "license": "public domain (NCBI)"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point (Netzsch SDS)",
      "value": 29.8,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "pressure": "not stated on the page"
      },
      "method": "Value printed in the SDS physical properties table",
      "status": "ground",
      "note": "The SDS prints 29.8°C with no space; the same SDS also notes a low melting point in its hazards section.",
      "source": "sds-netzsch",
      "where": "Section 9, row Melting point / Melting range",
      "source_detail": {
        "title": "NETZSCH safety data sheet, MSDS E Gallium 6.0 (EC 1907/2006 format)",
        "id": "Version 6.0, revision date 02.08.2022",
        "url": "https://analyzing-testing.netzsch.com/_Resources/Persistent/6/b/1/b/6b1b7407656ada04cf7ff8df6636921100b743d0/MSDS%20E%20Gallium%206.0.pdf",
        "year": 2022,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "boiling_point",
      "value": 2204,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "pressure": "760 mm Hg"
      },
      "method": "Value printed in the PubChem experimental properties record",
      "status": "ground",
      "source": "pubchem-gallium",
      "where": "Experimental Properties, Boiling Point (printed as 2204 °C @760 [mm Hg])",
      "source_detail": {
        "title": "PubChem compound record, Gallium (CID 5360835), JSON view",
        "id": "CID 5360835; CAS 7440-55-3",
        "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/5360835/JSON",
        "kind": "database",
        "license": "public domain (NCBI)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "value": 29,
      "bound": "exact",
      "unit": "W/(m K)",
      "scope": "material",
      "conditions": {
        "temperature": "not stated on the page"
      },
      "method": "Value printed in the Thermal properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Thermal properties, row Thermal Conductivity (also under Bulk physical properties)",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "specific_heat",
      "value": 371,
      "bound": "exact",
      "unit": "J/(kg K)",
      "scope": "material",
      "conditions": {
        "phase": "solid (the page notes that the value is given for the solid phase)"
      },
      "method": "Value printed in the Thermal properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Thermal properties, row Specific Heat and its note",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of linear thermal expansion (page label Thermal Expansion)",
      "value": 0.00012,
      "bound": "exact",
      "unit": "K-1",
      "scope": "material",
      "conditions": {
        "temperature": "not stated on the page"
      },
      "method": "Value printed as 0.00012 K -1 in the Thermal properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Thermal properties, row Thermal Expansion",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "heat_of_fusion",
      "label": "Heat of fusion (not in the canonical list)",
      "value": 5.59,
      "bound": "exact",
      "unit": "kJ/mol",
      "scope": "material",
      "conditions": {
        "state_change": "solid to liquid at the melting point"
      },
      "method": "Value printed in the Thermal properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Thermal properties, row Heat of Fusion",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "brinell_hardness",
      "label": "Brinell hardness (not in the canonical list)",
      "value": 60,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "test": "Brinell; test load and ball size not stated on the page"
      },
      "method": "Value printed in the Bulk physical properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Bulk physical properties, row Brinell Hardness",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "mohs_hardness",
      "label": "Mineral (Mohs) hardness (printed with no unit)",
      "value": 1.5,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "scale": "Mohs mineral hardness, as printed"
      },
      "method": "Value printed in the Hardnesses section; the page gives no unit",
      "status": "ground",
      "source": "webelements",
      "where": "Hardnesses, row Mineral hardness (printed as 1.5 (no units))",
      "source_detail": {
        "title": "WebElements Periodic Table: Gallium, physical properties",
        "id": "WebElements, Gallium - 31 Ga physical properties",
        "url": "https://www.webelements.com/gallium/physics.html",
        "year": 2026,
        "kind": "database",
        "license": "WebElements (Mark Winter), all rights reserved; cited, not reproduced"
      }
    },
    {
      "benchmark": "speed_of_sound",
      "label": "Speed of sound (not in the canonical list)",
      "value": 2740,
      "bound": "exact",
      "unit": "m/s",
      "scope": "material",
      "conditions": {
        "temperature": "not stated on the page"
      },
      "method": "Value printed in the Bulk physical properties table",
      "status": "ground",
      "source": "periodictable",
      "where": "Bulk physical properties, row Speed of Sound",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "electronegativity",
      "label": "Electronegativity (not in the canonical list; printed with no unit)",
      "value": 1.81,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "scale": "not stated on the page"
      },
      "method": "Value printed in the Reactivity table; the page gives no unit",
      "status": "ground",
      "source": "periodictable",
      "where": "Reactivity, row Electronegativity",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "atomic_weight",
      "label": "Standard atomic weight (not in the canonical list; printed with no unit)",
      "value": 69.723,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "basis": "standard atomic weight of natural gallium"
      },
      "method": "Value printed in the NIST table of atomic weights for gallium",
      "status": "ground",
      "uncertainty": "(1)",
      "source": "nist",
      "where": "Table for gallium, Standard Atomic Weight column (printed as 69.723(1))",
      "source_detail": {
        "title": "NIST Atomic Weights and Isotopic Compositions for Gallium",
        "id": "NIST Physical Measurement Laboratory, standard atomic weight",
        "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Ga&ascii=html&isotype=some",
        "kind": "database",
        "license": "US government data, public domain"
      }
    },
    {
      "benchmark": "atomic_radius",
      "label": "Atomic radius (not in the canonical list)",
      "value": 136,
      "bound": "exact",
      "unit": "pm",
      "scope": "material",
      "conditions": {
        "basis": "atomic radius as printed by the Periodic Table page"
      },
      "method": "Value printed in the Atomic dimensions and structure table",
      "status": "ground",
      "source": "periodictable",
      "where": "Atomic dimensions and structure, row Atomic Radius",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "vapor_pressure",
      "label": "Vapour pressure (not in the canonical list)",
      "value": 1,
      "bound": "exact",
      "unit": "Pa",
      "scope": "material",
      "conditions": {
        "temperature": "1037 °C"
      },
      "method": "Value printed in the PubChem experimental properties record (printed as 1 Pa @ 1037 °C; the record gives further pairs at higher temperatures)",
      "status": "ground",
      "source": "pubchem-gallium",
      "where": "Experimental Properties, Vapor Pressure",
      "source_detail": {
        "title": "PubChem compound record, Gallium (CID 5360835), JSON view",
        "id": "CID 5360835; CAS 7440-55-3",
        "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/5360835/JSON",
        "kind": "database",
        "license": "public domain (NCBI)"
      }
    },
    {
      "benchmark": "crustal_abundance",
      "label": "Abundance in Earth's crust (not in the canonical list)",
      "value": 0.0019,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "basis": "percent by mass in the Earth's crust, as printed"
      },
      "method": "Value printed in the Abundances table",
      "status": "ground",
      "source": "periodictable",
      "where": "Abundances, row % in Earth's Crust",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "isotopic_abundance",
      "label": "Natural abundance of gallium-69 (not in the canonical list)",
      "value": 60.108,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "isotope": "69Ga",
        "basis": "natural isotopic composition"
      },
      "method": "Value printed in the Isotopic Abundances table",
      "status": "ground",
      "source": "periodictable",
      "where": "Isotopic Abundances, row 69 Ga",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "isotopic_abundance",
      "label": "Natural abundance of gallium-71 (not in the canonical list)",
      "value": 39.892,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "isotope": "71Ga",
        "basis": "natural isotopic composition"
      },
      "method": "Value printed in the Isotopic Abundances table",
      "status": "ground",
      "source": "periodictable",
      "where": "Isotopic Abundances, row 71 Ga",
      "source_detail": {
        "title": "Periodic Table (periodictable.com): Gallium technical data",
        "id": "Element 31 data page",
        "url": "https://periodictable.com/Elements/031/data.html",
        "kind": "database",
        "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
      }
    },
    {
      "benchmark": "ld50_oral",
      "label": "Acute oral LD50 of gallium (not in the canonical list; a range as printed)",
      "value": 50,
      "value_high": 300,
      "bound": "range",
      "unit": "mg/kg",
      "scope": "material",
      "conditions": {
        "component": "Gallium",
        "species": "not stated in the SDS",
        "route": "oral"
      },
      "method": "Range printed in the SDS acute toxicity table",
      "status": "ground",
      "note": "The SDS gives no species or test method, so treat the range as a rough screening figure.",
      "source": "sds-labally",
      "where": "Section 11, Acute toxicity table, LD50 Oral for Gallium",
      "source_detail": {
        "title": "Lab Alley safety data sheet, Gallium Metal 99.99%",
        "id": "Issue date 07/22/2024, revision 0",
        "url": "https://media.laballey.com/docbuilder/gallium-metal-9999-safety-data-sheet-66a115cc271fd.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Dry air at room temperature",
      "headline": "Gallium is stable in dry air.",
      "effect": "The Isoflex SDS says gallium is stable in dry air and tarnishes in moist air or oxygen. The PubChem record says the same for moist air.",
      "rating": "none",
      "conditions": {
        "temperature": "room temperature",
        "exposure": "not stated"
      },
      "source": "sds-isoflex",
      "where": "Section 10, Chemical Stability"
    },
    {
      "environment": "Moist air or oxygen",
      "headline": "Gallium tarnishes in moist air.",
      "effect": "The Isoflex SDS says gallium 'tarnishes in moist air or oxygen', and PubChem says 'in moist air it tarnishes'. Tarnish is a surface change; the sources give no depth or rate.",
      "rating": "low",
      "conditions": {
        "exposure": "moist air or oxygen; time not stated"
      },
      "source": "sds-isoflex",
      "where": "Section 10, Chemical Stability; the same point appears in the PubChem Air and Water Reactions entry"
    },
    {
      "environment": "Aluminium and aluminium alloys",
      "headline": "Gallium forms an amalgam with aluminium alloys and corrodes aluminium.",
      "effect": "PubChem records gallium as corrosive to aluminum and says it forms an amalgam with aluminum alloys. The rating is our reading of that wording; the record gives no exposure time, temperature or rate.",
      "rating": "severe",
      "conditions": {
        "temperature": "not stated",
        "exposure": "not stated"
      },
      "source": "pubchem-gallium",
      "where": "Hazards Summary; Stability and Reactivity, Hazardous Reactivities and Incompatibilities"
    },
    {
      "environment": "Most metals, including at elevated temperature",
      "headline": "The Isoflex SDS says gallium is corrosive to most metals.",
      "effect": "The Isoflex SDS says gallium 'will dissolve the metal' and is 'corrosive to most metals'. PubChem says gallium is very corrosive to most metals at elevated temperature, but the temperature range printed in that record is garbled, so no temperature is used here.",
      "rating": "moderate",
      "conditions": {
        "temperature": "elevated, not given as a number",
        "exposure": "not stated"
      },
      "source": "sds-isoflex",
      "where": "Section 6, Methods for cleaning up"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "PubChem's aggregated GHS record for gallium lists H290, H302, H314 and H412 across company notifications, with the signal word Danger. The record says: 'This chemical does not meet GHS hazard criteria for 2.3% (9 of 388) of reports.'",
        "ghs": [
          "H290",
          "H302",
          "H314",
          "H412"
        ],
        "source": "pubchem-gallium",
        "where": "Hazards Identification, GHS Classification"
      },
      {
        "text": "The Netzsch safety data sheet classifies gallium as H290 (may be corrosive to metals), H302 (harmful if swallowed) and H412 (harmful to aquatic life with long lasting effects), with the signal word Warning.",
        "ghs": [
          "H290",
          "H302",
          "H412"
        ],
        "source": "sds-netzsch",
        "where": "Sections 2.1 and 2.2 (Classification and Label elements)"
      },
      {
        "text": "The Lab Alley safety data sheet lists corrosive to metals and acute oral toxicity classes, the signal word Warning, and the statements 'May be corrosive to metals. Harmful if swallowed.'",
        "ghs": [],
        "source": "sds-labally",
        "where": "Section 2.1 and 2.2 (Classification and Label elements)"
      },
      {
        "text": "The Isoflex safety data sheet describes gallium as irritating to the eyes, respiratory system and skin, and says its toxicological properties have not been fully investigated. The Netzsch sheet describes a caustic effect on skin and mucous membranes, so the two sheets disagree.",
        "ghs": [],
        "source": "sds-isoflex",
        "where": "Section 2, Emergency Overview and Potential Health Effects; Netzsch Section 11"
      }
    ],
    "failure_risks": [
      {
        "mode": "Melting in a warm environment",
        "trigger": "Temperature rising above the melting point of 29.8 °C given in the Netzsch SDS",
        "consequence": "The solid turns liquid and can flow. The Netzsch SDS warns that gallium has a low melting point and that melted gallium has to be handled with appropriate care.",
        "severity": "moderate",
        "source": "sds-netzsch",
        "where": "Section 2.3 (Other hazards) and Section 9"
      },
      {
        "mode": "Attack on aluminium parts and tools",
        "trigger": "Contact with aluminium or aluminium alloy parts, or with aluminium tools",
        "consequence": "Amalgam formation and corrosion of the aluminium, as recorded by PubChem",
        "severity": "high",
        "source": "pubchem-gallium",
        "where": "Hazardous Reactivities and Incompatibilities; Accidental Release Measures"
      },
      {
        "mode": "Violent reaction with halogens and strong oxidisers",
        "trigger": "Contact with halogens such as chlorine, or with hydrogen peroxide",
        "consequence": "PubChem reports a violent or vigorous reaction with halogens, and a potentially explosive reaction with hydrogen peroxide plus hydrochloric acid.",
        "severity": "high",
        "source": "pubchem-gallium",
        "where": "Stability and Reactivity, Reactivity Profile; Hazardous Reactivities and Incompatibilities"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Keep the container tightly closed, under an inert atmosphere, in a dry and well-ventilated place, and refrigerated to maintain quality.",
        "source": "sds-labally",
        "where": "Section 7.2 (Conditions for safe storage)"
      },
      {
        "text": "Do not use steel or aluminium tools or equipment with gallium, and cover spills with non-combustible material, as PubChem's safety record advises.",
        "source": "pubchem-gallium",
        "where": "Accidental Release Measures, Preventive Measures"
      },
      {
        "text": "Avoid generating dust and provide ventilation where the metal is cleaned up or handled.",
        "source": "sds-isoflex",
        "where": "Section 6 (Methods for cleaning up) and Section 7 (Handling and storage)"
      }
    ],
    "mitigations": []
  },
  "uses": [
    {
      "application": "electronics-and-chips",
      "device": "Integrated circuits and optoelectronic devices made from gallium arsenide and gallium nitride",
      "example": "USGS reports that integrated circuits are the largest domestic use of gallium, ahead of optoelectronic devices.",
      "source": "usgs-mcs2026-gallium",
      "where": "Domestic Production and Use"
    },
    {
      "application": "optics-and-cameras",
      "device": "Laser diodes, light-emitting diodes and photodetectors made from gallium arsenide or gallium nitride",
      "example": "USGS says optoelectronic devices were used in aerospace applications, consumer goods, industrial equipment, medical equipment and telecommunications equipment.",
      "source": "usgs-mcs2026-gallium",
      "where": "Domestic Production and Use"
    },
    {
      "application": "solar-arrays",
      "device": "Gallium arsenide solar cells",
      "example": "USGS says silicon is the principal competitor with GaAs in solar-cell applications.",
      "source": "usgs-mcs2026-gallium",
      "where": "Substitutes"
    }
  ],
  "supply": [
    {
      "subject": "Gallium",
      "abundance": "Earth's crust 0.0019 % by mass (Periodic Table). USGS: 'The average gallium content of bauxite is 50 parts per million.'",
      "producers": [
        {
          "country": "China",
          "share_percent": 99,
          "year": 2025
        },
        {
          "country": "Japan",
          "year": 2025
        },
        {
          "country": "Russia",
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals (entry: Gallium, used in semiconductors)",
          "listed": true
        },
        {
          "list": "EU critical raw materials list (Regulation (EU) 2024/1252)",
          "listed": true
        }
      ],
      "recycling": "USGS: 'Old scrap, none.' New scrap from the manufacture of GaAs-based devices is reprocessed to recover high-purity gallium at one facility in New York.",
      "substitutes": [
        "USGS: silicon is the principal competitor with GaAs in solar-cell applications.",
        "USGS: no effective substitutes exist for GaAs and GaN in the defence-related applications where they are used."
      ],
      "source": "usgs-mcs2026-gallium",
      "where": "World Low-Purity Production table; Events, Trends, and Issues (the sentence 'China accounted for 99% of worldwide primary low-purity gallium production' prints no year, so 2025 is the reporting year used here; Japan and Russia are named in the same paragraph); Recycling; Substitutes. Critical lists: USGS 2025 final list page and European Commission page (see sources)."
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "USGS Mineral Commodity Summaries 2026: Gallium",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-gallium.pdf",
      "year": 2026
    },
    {
      "title": "PubChem compound record, Gallium (CID 5360835)",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/5360835",
      "year": 2026
    },
    {
      "title": "Lab Alley safety data sheet, Gallium Metal 99.99%",
      "type": "sds",
      "url": "https://media.laballey.com/docbuilder/gallium-metal-9999-safety-data-sheet-66a115cc271fd.pdf",
      "year": 2024
    },
    {
      "title": "NETZSCH MSDS E Gallium, version 6.0",
      "type": "sds",
      "url": "https://analyzing-testing.netzsch.com/_Resources/Persistent/6/b/1/b/6b1b7407656ada04cf7ff8df6636921100b743d0/MSDS%20E%20Gallium%206.0.pdf",
      "year": 2022
    },
    {
      "title": "ISOFLEX safety data sheet, Gallium, Enriched Gallium (version 1.3)",
      "type": "sds",
      "url": "https://www.isoflex.com/docman-all-categories/sds/527-gallium-rev-4/file",
      "year": 2024
    },
    {
      "title": "NIST Atomic Weights and Isotopic Compositions for Gallium",
      "type": "database",
      "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Ga&ascii=html&isotype=some"
    }
  ],
  "gaps": [
    "Electrical resistivity and electrical conductivity are printed in exponent form on the pages read (WebElements and the Periodic Table), so no value is recorded for them.",
    "Young's modulus, shear and bulk modulus and Vickers hardness have no data on the WebElements page; no tensile, creep or fatigue data for solid gallium were found in the sources read.",
    "The WebElements coefficient of linear thermal expansion is printed in exponent form and is not used; the Periodic Table value is recorded instead, with its own page label.",
    "The Lab Alley SDS gives its melting point in degrees Celsius and Fahrenheit and gives 'No information available' for density, so neither is used as a row from that sheet.",
    "Liquid density has no stated temperature on the Periodic Table page, and PubChem gives a liquid value without a printed unit, so only the Periodic Table value is recorded for the liquid.",
    "The electronegativity scale is not stated on the Periodic Table page.",
    "No corrosion-rate, exposure-time or test data for gallium on aluminium or other metals were found in the sources read; the corrosion ratings are qualitative readings of the sources' wording.",
    "No flight, vacuum, radiation or space-environment data for elemental gallium were found in the sources read. Its space use is through gallium arsenide and gallium nitride, which have their own profiles.",
    "No UNS, EN or other grade designation applies to gallium metal in the sources read, so none is listed.",
    "The USGS production table text is partly garbled in the PDF; the China share is taken from the sentence in the Events section, and no 2025 share is computed from the table.",
    "The USGS 2025 critical-minerals and EU critical-raw-materials list entries were read from a web summary of each page and should be checked against the printed list before they are cited in a report.",
    "The NIST table prints the isotope composition in a spaced form that does not parse cleanly, so the Periodic Table isotope values are used instead.",
    "The PubChem record gives a single vapour-pressure pair (1 Pa at 1037 °C) in the text read, with other pairs at higher temperatures that were not used.",
    "The heat of fusion value is from the Periodic Table only; no second source for it was opened."
  ],
  "story": {
    "why": "Gallium (Ga) melts at 29.8 °C in the Netzsch safety data sheet, close to the 29.76 °C and 29.78 °C given by the other two sources, so the metal can turn liquid in a warm room. In electronics, the element matters as feedstock. The USGS says gallium is used through gallium arsenide and gallium nitride, for integrated circuits and optoelectronic devices such as LEDs, laser diodes and photodetectors. This profile covers the element only; the compounds have their own profiles (gallium arsenide, gallium nitride and gallium oxide).",
    "uses": [
      {
        "where": "Chips and optoelectronics",
        "line": "USGS reports that integrated circuits are the largest domestic use of gallium, with optoelectronic devices second. Gallium arsenide and gallium nitride are the two compound forms it names."
      },
      {
        "where": "Light-emitting and laser devices",
        "line": "USGS lists laser diodes, light-emitting diodes and photodetectors among the optoelectronic devices made from gallium compounds, and says optoelectronic devices were used in aerospace applications."
      },
      {
        "where": "Solar cells",
        "line": "USGS names silicon as the principal competitor with gallium arsenide in solar-cell applications."
      }
    ],
    "can_do": [
      {
        "label": "Melting point",
        "line": "Gallium melts at 29.76 °C (Periodic Table), 29.78 °C (PubChem) and 29.8 °C (Netzsch SDS). The three values agree to one decimal place, and the second decimal place differs between the sources.",
        "scope": "material"
      },
      {
        "label": "Density",
        "line": "The solid has a density of 5.904 g/cm3 at 20 °C (Netzsch SDS). The liquid has a density of 6.095 g/cm3 (Periodic Table), with no temperature stated.",
        "scope": "material"
      },
      {
        "label": "Heat conduction",
        "line": "The metal conducts heat at 29 W/(m K) (Periodic Table), with no temperature stated on the page.",
        "scope": "material"
      },
      {
        "label": "Boiling point",
        "line": "Gallium boils at 2204 °C at 760 mm Hg (PubChem).",
        "scope": "material"
      }
    ],
    "compare": "Read together, the printed values show that solid gallium is less dense than liquid gallium: 5.904 g/cm3 for the solid at 20 °C (Netzsch SDS) against 6.095 g/cm3 for the liquid (Periodic Table, temperature not stated). A solid piece would therefore float on its own melt, though the two densities come from different sources and temperatures. The sources also disagree on the melting point in the second decimal place: 29.76 °C (Periodic Table), 29.78 °C (PubChem) and 29.8 °C (Netzsch SDS). The differences are small, but the value for a given grade should come from its supplier's certificate.",
    "compare_rows": [
      {
        "label": "Melting point",
        "benchmark": "melting_point",
        "scope": "material"
      },
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Thermal conductivity",
        "benchmark": "thermal_conductivity",
        "scope": "material"
      }
    ],
    "handling": [
      "Store the metal tightly closed under an inert atmosphere and refrigerated, as the Lab Alley sheet directs.",
      "Do not use steel or aluminium tools with it, because gallium attacks aluminium (PubChem).",
      "Avoid dust and provide ventilation where the metal is handled or cleaned up (Isoflex sheet).",
      "Take care with melted metal, which the Netzsch sheet says needs appropriate care."
    ],
    "good_for": [
      "Semiconductor feedstock. USGS describes gallium arsenide and gallium nitride as the forms used for chips and optoelectronic devices.",
      "Light-emitting and laser devices. USGS lists LEDs and laser diodes among the optoelectronic devices made from gallium compounds."
    ],
    "watch_out": [
      "Melting point near room temperature: the solid turns liquid at 29.8 °C (Netzsch SDS), so a sample can change state in a warm room.",
      "Corrosion of aluminium: gallium forms an amalgam with aluminium alloys (PubChem).",
      "Conflicting hazard labels: PubChem's aggregated reports show H314 and a Danger label, while the safety data sheets read here use Warning.",
      "Thin toxicity data: the Isoflex sheet says its toxicological properties have not been fully investigated."
    ],
    "verdict": "Gallium is a low-melting metal whose main value is as feedstock for gallium arsenide and gallium nitride chips and LEDs. Handle the metal as corrosive to aluminium and to most metals, and check the supplier's safety sheet for the grade you buy.",
    "recipe": {
      "line": "Gallium is a single element, symbol Ga. The USGS says primary gallium is recovered predominantly as a byproduct of processing bauxite ores, with some from zinc-processing residues. Natural gallium is a mix of two stable isotopes: 69Ga at 60.108% and 71Ga at 39.892% (Periodic Table).",
      "parts": [
        {
          "name": "Gallium",
          "symbol": "Ga",
          "role": "The whole metal. It is a single element, so there is no alloying element in this profile; the atomic weight is the NIST standard value.",
          "atoms": 1,
          "atomic_weight": 69.723
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The safety data sheets read for this profile give a Warning label with H290 and H302. PubChem's aggregated reports add H314 (severe skin burns) with a Danger label.",
        "points": [
          {
            "label": "Ingestion",
            "line": "The Lab Alley sheet gives an oral LD50 range of 50 to 300 mg/kg for gallium, with no species or test named. The sheets classify it as harmful if swallowed (H302)."
          },
          {
            "label": "Skin and eyes",
            "line": "The Isoflex sheet calls the metal irritating to the eyes, respiratory system and skin. The Netzsch sheet describes a caustic effect on skin and mucous membranes. The two sheets do not agree."
          },
          {
            "label": "Dust and fire",
            "line": "Avoid dust. In a fire, decomposition gives irritating and toxic fumes and gases, according to the Isoflex sheet."
          }
        ],
        "level": 1,
        "verdict": "Harmful if swallowed; corrosive to metals"
      },
      {
        "title": "If the metal melts or spills",
        "lead": "Above its melting point the metal is a liquid, and it can attack other metals.",
        "points": [
          {
            "label": "Aluminium",
            "line": "PubChem says gallium is corrosive to aluminum and forms an amalgam with aluminum alloys. It advises against steel and aluminum tools."
          },
          {
            "label": "Cleanup",
            "line": "The Isoflex sheet advises cooling spilled metal so that it solidifies before cleanup, and protecting metal construction from contact."
          }
        ],
        "level": 2,
        "verdict": "Liquid metal attacks aluminium"
      },
      {
        "title": "Handling and storage",
        "lead": "Store the metal closed, dry and refrigerated, and keep it away from metals and oxidising agents.",
        "points": [
          {
            "label": "Storage",
            "line": "The Lab Alley sheet calls for a tightly closed container under an inert atmosphere and refrigeration."
          },
          {
            "label": "Moist air",
            "line": "Gallium tarnishes in moist air, according to the Isoflex sheet and PubChem."
          }
        ]
      }
    ]
  },
  "updated": "2026-11-01",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 21,
    "unreachable": 0,
    "caveats": 3,
    "note": "Written by an AI assistant on 2026-11-01 from pages read in this run. Three melting-point values and two density values differ or lack a printed unit; each is kept with its source. Values with exponent form are left out."
  },
  "sources": {
    "webelements": {
      "title": "WebElements Periodic Table: Gallium, physical properties",
      "id": "WebElements, Gallium - 31 Ga physical properties",
      "url": "https://www.webelements.com/gallium/physics.html",
      "year": 2026,
      "kind": "database",
      "license": "WebElements (Mark Winter), all rights reserved; cited, not reproduced"
    },
    "periodictable": {
      "title": "Periodic Table (periodictable.com): Gallium technical data",
      "id": "Element 31 data page",
      "url": "https://periodictable.com/Elements/031/data.html",
      "kind": "database",
      "license": "Web page, cited not reproduced; values from Mathematica ElementData per the page"
    },
    "nist": {
      "title": "NIST Atomic Weights and Isotopic Compositions for Gallium",
      "id": "NIST Physical Measurement Laboratory, standard atomic weight",
      "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Ga&ascii=html&isotype=some",
      "kind": "database",
      "license": "US government data, public domain"
    },
    "pubchem-gallium": {
      "title": "PubChem compound record, Gallium (CID 5360835), JSON view",
      "id": "CID 5360835; CAS 7440-55-3",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/5360835/JSON",
      "kind": "database",
      "license": "public domain (NCBI)"
    },
    "usgs-mcs2026-gallium": {
      "title": "Mineral Commodity Summaries 2026, Gallium",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-gallium.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "sds-labally": {
      "title": "Lab Alley safety data sheet, Gallium Metal 99.99%",
      "id": "Issue date 07/22/2024, revision 0",
      "url": "https://media.laballey.com/docbuilder/gallium-metal-9999-safety-data-sheet-66a115cc271fd.pdf",
      "year": 2024,
      "kind": "datasheet",
      "license": "supplier document, linked not reproduced"
    },
    "sds-netzsch": {
      "title": "NETZSCH safety data sheet, MSDS E Gallium 6.0 (EC 1907/2006 format)",
      "id": "Version 6.0, revision date 02.08.2022",
      "url": "https://analyzing-testing.netzsch.com/_Resources/Persistent/6/b/1/b/6b1b7407656ada04cf7ff8df6636921100b743d0/MSDS%20E%20Gallium%206.0.pdf",
      "year": 2022,
      "kind": "datasheet",
      "license": "supplier document, linked not reproduced"
    },
    "sds-isoflex": {
      "title": "ISOFLEX safety data sheet, Gallium, Enriched Gallium (version 1.3)",
      "id": "Revision date 05/10/2024, revision number 3",
      "url": "https://www.isoflex.com/docman-all-categories/sds/527-gallium-rev-4/file",
      "year": 2024,
      "kind": "datasheet",
      "license": "supplier document, linked not reproduced"
    },
    "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), Regulation (EU) 2024/1252",
      "id": "Regulation (EU) 2024/1252",
      "url": "https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en",
      "year": 2024,
      "kind": "web",
      "license": "European Commission web page, cited not reproduced"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/gallium/"
}