RocksdayEmerald vs Grossular
How to tell them apart
Green beryl colored by chromium or vanadium — one of the four classic precious gems.
Photo: Géry PARENT, CC0
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
Quick tests
- Heft: Grossular feels noticeably heavier for its size (specific gravity 3.57–3.73 vs 2.67–2.78).
Key differences
- Emerald forms hexagonal prisms.
Side by side
| Property | Emerald | Grossular |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 7.5–8 | 6.5–7.5 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Green | Green, Orange, Brown, Pink |
| Crystal system | Hexagonal | Cubic |
| Specific gravity | 2.67–2.78 | 3.57–3.73 |
| Formula | Be₃Al₂Si₆O₁₈ (with Cr/V) | Ca₃Al₂(SiO₄)₃ |
| Found in | Muzo and Chivor, Colombia; Kafubu, Zambia | Tsavo, Kenya; Tanzania |
Properties that are the same for both are grayed out.
How to identify emerald
- Deep green six-sided prisms with flat ends.
- Almost always has internal fractures and inclusions.
- Hardness 7.5–8.
Crystal system: Hexagonal
Full Emerald guide →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 →More comparisons
Could you tell them apart from a blurry close-up?
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