Emerald
The green jewel of royalty, prized for its saturated color above all else.
Emerald is the green variety of the mineral beryl, colored by trace amounts of chromium and sometimes vanadium. It completes the 'big four' precious gemstones alongside diamond, ruby, and sapphire. Unlike other precious stones where clarity is paramount, the trade accepts visible inclusions in emerald — the French term 'jardin' (garden) describes the characteristic internal landscape. Colombian emeralds set the color standard with their pure, vivid green, while Zambian stones are known for a slightly bluish-green hue and superior clarity. Nearly all emeralds are oiled or treated to improve appearance.
Physical Properties
| Hardness (Mohs) | 7.5–8 |
| Refractive Index | 1.565–1.602 |
| Specific Gravity | 2.67–2.78 |
| Crystal System | Hexagonal |
| Chemical Formula | Be₃Al₂(SiO₃)₆ |
Color Varieties
Major Sources
Colombia · Zambia · Brazil · Ethiopia · Zimbabwe · Afghanistan
Pricing Factors
Color
The single most important factor. Vivid, saturated green without being too dark or too light commands the highest prices. Colombian 'muzo' green is the benchmark.
Clarity
Eye-clean emeralds are rare and exponentially more valuable. The trade is more tolerant of inclusions in emerald than any other precious stone.
Treatment
Minor oiling is industry standard and expected. Heavily oiled or resin-treated stones are discounted. 'No oil' emeralds from top labs carry massive premiums.
Origin
Colombian origin carries the strongest premium. Zambian emeralds offer excellent quality at lower prices. Ethiopian material is newer to market and more affordable.
Care Instructions
Do
- Clean gently with lukewarm soapy water and a very soft cloth
- Store in a padded box away from other jewelry
- Re-oil periodically through a trusted jeweler to maintain appearance
Don't
- Never use ultrasonic or steam cleaners — emeralds are almost always treated and these methods can damage fillings
- Don't expose to heat or sudden temperature changes
- Avoid harsh chemicals, solvents, and acetone which can strip oil treatment
Cleaning Method
Only use lukewarm soapy water with a very soft cloth. Emeralds are the most fragile of the precious gemstones and require the gentlest care.
Insider Buying Tips
Accept that inclusions are normal in emerald — focus on color first, then clarity.
Request a lab report that discloses the level of enhancement (none, minor, moderate, significant).
Zambian emeralds offer the best value for buyers who prefer a slightly bluish-green hue.
Avoid setting emeralds in tension settings or high-exposure ring designs — they chip more easily than other precious stones.
For large emeralds (3+ carats), even moderate inclusions are acceptable if the color is exceptional.
Did You Know?
Cleopatra was famously obsessed with emeralds and claimed ownership of all Egyptian emerald mines.
The Mogul Mughal Emerald, dating to 1695, sold for $2.2 million at Christie's.
Colombia produces roughly 70–90% of the world's fine emeralds.