Definition
What is Emerald?
Emerald is the green to bluish-green gem variety of beryl. Chromium and/or vanadium substituting in the crystal structure are associated with emerald color. Because natural emeralds commonly contain fractures and inclusions, clarity enhancement and careful wear require explicit treatment and care discussion.
At a glance
Gemological properties
Values marked pending have not yet cleared the editorial source review.
| Gemstone name | Emerald | Mineral species | Beryl |
|---|---|---|---|
| Chemical formula | Be₃Al₂Si₆O₁₈ | Crystal system | Hexagonal |
| Mohs hardness | 7.5–8 | Specific gravity | 2.72 |
| Refractive index | 1.577–1.583 | Birefringence | 0.005–0.009 |
| Primary color | Green | Optical character | Pending verification |
| Luster | Pending verification | Transparency | Pending verification |
Science & context
A layered reference
What is Emerald?
Emerald is the green to bluish-green gem variety of beryl. Chromium and/or vanadium substituting in the crystal structure are associated with emerald color. Because natural emeralds commonly contain fractures and inclusions, clarity enhancement and careful wear require explicit treatment and care discussion.
Evidence
References & further reading
- [1]Emerald Gemstone Overview
Gemological Institute of America
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