Calcium-aluminum garnet occurring in a wide range of colors. Tsavorite green and hessonite orange are prized gem varieties. Color: Green, orange, yellow, brown, colorless. Luster: Vitreous to resinous. Streak: White. Cleavage: None. Hardness: 6.5-7.5. Transparency: Transparent to translucent. Crystal system: Isometric Cubic. Chemical formula: Ca₃Al₂ SiO₄ ₃. Specific gravity: 3.4-3.6. Formation: Forms in contact metamorphism of impure calcareous rocks skarns and in some serpentinites. Common geological settings: Kenya tsavorite , Sri Lanka hessonite , Canada, Mexico; found in skarns and metamorphic limestones. Common look-alikes and related entries: Epidote, Vesuvianite, Diopside.
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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
2026-03-30T14:36:48.018204+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.
Calcium-aluminum garnet occurring in a wide range of colors. Tsavorite green and hessonite orange are prized gem varieties.
How can you identify Grossular?
Compare several properties rather than relying on colour alone. This entry records colour: Green, orange, yellow, brown, colorless; lustre: Vitreous to resinous; streak: White; Mohs hardness: 6.5-7.5; cleavage: None; crystal system: Isometric Cubic; transparency: Transparent to translucent. Confirm an important identification with additional field tests or qualified laboratory work.
How does Grossular form?
Forms in contact metamorphism of impure calcareous rocks skarns and in some serpentinites.
Where is Grossular commonly found?
Kenya tsavorite , Sri Lanka hessonite , Canada, Mexico; found in skarns and metamorphic limestones.
What is Grossular commonly confused with?
Grossular may be confused with Epidote, Vesuvianite, Diopside. Compare multiple diagnostic properties because colour and surface appearance can overlap.
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