RocksdayAquamarine vs Euclase
To tell Aquamarine from Euclase: Aquamarine is hexagonal and does not have this cleavage.
Pale blue to sea-green beryl, often growing as clean, long hexagonal crystals.
Photo: Gunnar Ries Amphibol, CC BY-SA 2.5
A hard beryllium silicate, usually pale blue or colorless, with one perfect cleavage that makes it risky to set in jewelry.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Key differences
- Aquamarine is hexagonal and does not have this cleavage.
Side by side
| Property | Aquamarine | Euclase |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 7.5–8 | 7.5 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Blue, Green | Blue, Green, White, Clear |
| Crystal system | Hexagonal | Monoclinic |
| Specific gravity | 2.66–2.8 | 3–3.1 |
| Formula | Be₃Al₂Si₆O₁₈ (with Fe) | BeAlSiO₄(OH) |
| Found in | Minas Gerais, Brazil; Shigar Valley, Pakistan | Minas Gerais, Brazil; Chivor, Colombia |
Properties that are the same for both are grayed out.
How to identify aquamarine
- Sea-blue, glassy six-sided prisms.
- Hardness 7.5–8.
- Often very clean and transparent.
Crystal system: Hexagonal
Full Aquamarine guide →How to identify euclase
- Pale blue or colorless prismatic crystals.
- Hardness 7.5, but it splits on a flat plane if bumped.
- Heavier than beryl of the same size.
Crystal system: Monoclinic
Full Euclase guide →More comparisons
Frequently asked questions
What is the difference between aquamarine and euclase?
Aquamarine is a mineral with a Mohs hardness of 7.5–8 and a vitreous luster, usually blue or green. Euclase is a mineral with a Mohs hardness of 7.5 and a vitreous luster, usually blue, green, white or colorless.
How can you tell aquamarine from euclase?
Aquamarine is hexagonal and does not have this cleavage.
Could you tell them apart from a blurry close-up?
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