RocksdayGrossular vs Spessartine
How to tell them apart
Calcium aluminum garnet in more colors than any other garnet — green tsavorite and cinnamon hessonite are the best known.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Orange manganese garnet, prized in its bright 'mandarin' color.
Photo: Géry PARENT, Public domain
Key differences
- Spessartine is a purer, brighter orange.
- Hessonite grossular is browner and looks swirly inside.
Side by side
| Property | Grossular | Spessartine |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6.5–7.5 | 7–7.5 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Green, Orange, Brown, Pink | Orange, Red, Brown |
| Crystal system | Cubic | Cubic |
| Specific gravity | 3.57–3.73 | 4.12–4.18 |
| Formula | Ca₃Al₂(SiO₄)₃ | Mn₃Al₂(SiO₄)₃ |
| Found in | Tsavo, Kenya; Tanzania | Kunene, Namibia; Nigeria |
Properties that are the same for both are grayed out.
How to identify grossular
- Rounded garnet crystals in green, orange, pink or brown.
- Hardness about 7.
- Hessonite often looks 'swirly' inside, like syrup in water.
Crystal system: Cubic
Full Grossular guide →How to identify spessartine
- Vivid orange to red-orange.
- Many-faced rounded crystals, often on smoky quartz or feldspar.
- Hardness 7–7.5.
Crystal system: Cubic
Full Spessartine guide →More comparisons
Could you tell them apart from a blurry close-up?
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