Magnesium carbonate used in the production of refractory bricks and as a source of magnesium oxide. Color: White, yellowish, brownish. Luster: Vitreous to earthy. Streak: White. Cleavage: Perfect rhombohedral. Hardness: 3.5-4.5. Transparency: Transparent to opaque. Crystal system: Hexagonal Trigonal. Chemical formula: MgCO₃. Specific gravity: 2.98-3.02. Formation: Forms from alteration of magnesium-rich rocks by carbonate-bearing solutions, or by replacement of calcite. Common geological settings: Austria, China, Brazil, India; found in ultramafic rock sequences and evaporite deposits. Common look-alikes and related entries: Dolomite, Calcite, Siderite.
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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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Last updated
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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.
Magnesium carbonate used in the production of refractory bricks and as a source of magnesium oxide.
How can you identify Magnesite?
Compare several properties rather than relying on colour alone. This entry records colour: White, yellowish, brownish; lustre: Vitreous to earthy; streak: White; Mohs hardness: 3.5-4.5; cleavage: Perfect rhombohedral; crystal system: Hexagonal Trigonal; transparency: Transparent to opaque. Confirm an important identification with additional field tests or qualified laboratory work.
How does Magnesite form?
Forms from alteration of magnesium-rich rocks by carbonate-bearing solutions, or by replacement of calcite.
Where is Magnesite commonly found?
Austria, China, Brazil, India; found in ultramafic rock sequences and evaporite deposits.
What is Magnesite commonly confused with?
Magnesite may be confused with Dolomite, Calcite, Siderite. Compare multiple diagnostic properties because colour and surface appearance can overlap.
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