Emerald is the distinctive grass-green birthstone for May. While Colombian emeralds are considered the world's finest for their extraordinary color and crystallization, early examples from an exciting recent emerald discovery in China appear to rival the color and quality of the famous Colombian Muzo emeralds.
|Emeralds have a strong 7.5 to 8 ranking on Mohs' hardness scale. However, because emeralds are usually oiled or otherwise fracture-filled for better clarity, care should be taken to avoid sudden temperature changes, ultrasonic cleaners, and chemical cleaners. Emeralds are best cleaned with a soft cloth or cool water and a very soft brush.|
|Emeralds occur in various shades of green, slightly bluish-green, and even very slightly yellowish-green, including the famous grassy "emerald" green. |
|Jardin, the French word for "garden," is the name used in the industry to refer to inclusions in emeralds. Because of the nature of this type III gemstone, it is accepted that emeralds are commonly included. Rather than detracting from a stone's value, those jardin are viewed as an easy way to distinguish a natural emerald from a synthetic. It is also understood that nearly all emeralds have been treated to improve their clarity.|
Name Origin and Meaning
The name "emerald" is derived from the Greek word smaragados meaning "green stone." Many other green stones were also given this name in ancient times, before modern gemological testing allowed for gemstones to be classified in ways other than by color alone.
In rare cases, the internal characteristics of an emerald can create chatoyancy (the cat's-eye effect) when the gem is cut en cabochon. Also, in Colombia, dark carbonaceous material is sometimes trapped between emerald crystals during growth, resulting in unique Trapiche emeralds. When carefully cut and polished en cabochon, the dark lines form distinctive star- or wheel-like patterns.
Discovery and History
Emeralds were discovered so long ago--thousands and thousands of years ago--that the details of their discovery are unknown. While no definitive records exist, Cleopatra's emerald mines, in upper Egypt east of Aswan, are believed to have been worked as early as 2000 B.C. Even more astounding is the fact that emeralds are believed to be the first gems traded in markets in Babylon around 4000 B.C., adding a couple thousand years more to emerald's long, rich history.
This brooch displays a rare collection of chatoyant or cat's-eye emeralds, which occur when the internal characteristics of an emerald are aligned in such a way as to create a cat's-eye effect when the gem is cut en cabochon.
The emerald cut was designed specifically for emeralds. Because emerald is somewhat fragile, the corners of the rectangular shapes were cut off to prevent breakage.
A museum in Vienna houses an entire vase cut from a single emerald that weighs 2,205 carats and measures 4-3/4 inches tall.