Gemstone profile and identification guide
Grossular
Grossular is a calcium-aluminum garnet species including tsavorite and hessonite varieties.
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Overview
Grossular is a calcium-aluminum garnet species including tsavorite and hessonite varieties.
Did you know? Grossular includes both vividly green tsavorite and warm orange hessonite trade varieties.
Use this profile as a collector reference and educational guide for quick on-page comparison, then validate with the interactive identification system.
Identification
Name: Grossular
Scientific classification: Silicate (Garnet Group: Grossular)
Hardness: 7 Mohs
Transparency: transparent
Lustre: vitreous
Crystal system: Isometric (Cubic)
Primary colour: Green
Secondary colour: Yellow
Colour family: Greens
Cubic garnet behavior with grossular chemistry and RI/SG values identify species.
Verification Status
Status: verified-core-fields
Reference priority: GIA, Gem-A, Mindat, International Gem Society
Core identity, locality, and physical-property fields reviewed against standard gemological references.
Trade-name entries include conservative composition/treatment disclosures where needed.
Physical Properties
Hardness category: hard
Hardness value: 7 Mohs
Chemical composition: Calcium aluminum silicate [Ca3Al2(SiO4)3]
Crystal system: Isometric (Cubic)
Common locations: Kenya, Tanzania, Mali, Sri Lanka, Pakistan
Learn more: Gem-A gemstone education resources.
Colour Variations
Grossular garnet species spanning green, yellow, orange, and brown hues.
Optical effects: None specified in the current dataset.
Detailed Gemology
Mineral species: Grossular
Mineral group: Garnet group
Chemical formula: Calcium aluminum silicate [Ca3Al2(SiO4)3]
Mohs hardness: 7
Crystal system: Isometric (Cubic)
Lustre: vitreous
Transparency: transparent
Streak: White
Cleavage: None
Fracture: Conchoidal to uneven
Specific gravity: 3.57-3.73
Refractive index: 1.73-1.76
Optical phenomena: None typically diagnostic
Colour range: Green, yellow, orange, brown
Common inclusions: Crystals, needles, fingerprint inclusions
Geological environment: Metamorphic calc-silicate and skarn systems
Principal mining regions: Kenya, Tanzania, Mali, Sri Lanka, Pakistan
Important commercial sources: Gem grossular is sourced from East African and Asian metamorphic terrains
Historical significance: Important garnet species in modern colored gem trade.
Common treatments: Generally untreated.
Synthetic or imitation forms: Glass and synthetic garnet-like materials can imitate.
Common look-alikes: Andradite, sphene, zircon
Jewellery uses: Used in faceted gemstones and collector pieces.
Care recommendations: Durable for jewelry; avoid harsh impact on included stones.
Cross-check profile data with GIA Gem Encyclopedia and Mindat entry for Grossular.
Formation
Forms in metamorphic calc-silicate rocks and contact metasomatic settings.
Origin
Gem grossular is sourced from East African and Asian metamorphic terrains
Uses
Best for: Used in faceted gemstones and collector pieces.
Ideal uses: Fine jewelry and species-focused garnet collections.
Care
Durable for jewelry; avoid harsh impact on included stones.
Need another candidate? Use advanced gemstone search or return to the identification guide.
Related gemstones by colour
Related gemstones by hardness
Commonly confused gemstones
Grossular FAQ
How can I identify Grossular?
Compare hardness (7 Mohs), crystal system (Isometric (Cubic)), colour profile, and lustre (vitreous) with your sample. Then cross-check related gemstones listed above.
What colour range does Grossular appear in?
Grossular garnet species spanning green, yellow, orange, and brown hues.
Where is Grossular commonly used?
Fine jewelry and species-focused garnet collections.. For maintenance, follow the care guidance in this profile.
Scientific References
GIA: general gemstone identity (reviewed) - Batch 06 factual verification pass.
Gem-A: gemological terminology and testing references (reviewed) - Batch 06 factual verification pass.
Mindat: mineral species and principal localities (reviewed) - Batch 06 factual verification pass.
International Gem Society: gem trade context and treatment overview (reviewed) - Batch 06 factual verification pass.