Hydrated sodium borate forming in evaporite deposits. Major source of boron for glass, ceramics, and cleaning products. Color: Colorless, white, gray, yellowish. Luster: Vitreous to earthy. Streak: White. Cleavage: Perfect in one direction. Hardness: 2-2.5. Transparency: Transparent to translucent. Crystal system: Monoclinic. Chemical formula: Na₂B₄O₇·10H₂O. Specific gravity: 1.71. Formation: Precipitates from evaporating lakes in arid regions with volcanic-derived boron. Common geological settings: Turkey, California USA , Argentina, Chile; found in dried lake beds playas in arid regions. Common look-alikes and related entries: Ulexite, Calcite, Gypsum.
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These authoritative resources support category-level nomenclature, terminology, identification methods, and safety. When a specimen-specific safety warning appears, the public-health source listed here directly supports that precaution. They are not line-by-line citations for every other property on this entry, and natural specimens vary.
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GeoMiner
Last updated
2026-03-30T14:37:10.337371+00:00
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Published; not independently peer-reviewed
IMA–CNMNC List of Mineral Names — International Mineralogical Association. Official mineral-name, nomenclature, and classification records.
Mineral ID Key — Mineralogical Society of America. Physical-property identification methods, repeat-testing guidance, and limitations.
Hydrated sodium borate forming in evaporite deposits. Major source of boron for glass, ceramics, and cleaning products.
How can you identify Borax?
Compare several properties rather than relying on colour alone. This entry records colour: Colorless, white, gray, yellowish; lustre: Vitreous to earthy; streak: White; Mohs hardness: 2-2.5; cleavage: Perfect in one direction; crystal system: Monoclinic; transparency: Transparent to translucent. Confirm an important identification with additional field tests or qualified laboratory work.
How does Borax form?
Precipitates from evaporating lakes in arid regions with volcanic-derived boron.
Where is Borax commonly found?
Turkey, California USA , Argentina, Chile; found in dried lake beds playas in arid regions.
What is Borax commonly confused with?
Borax may be confused with Ulexite, Calcite, Gypsum. Compare multiple diagnostic properties because colour and surface appearance can overlap.
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