Emerald: Think Green |
As early as 4000 BC the emerald was traded in one of the earliest recorded gem markets in Babylon, but they are not of the quality they are today. Emeralds from Zimbabwe are also some of the oldest in the world, over 2600 million years old; and some from Pakistan, nine million years old, but again they do not measure up to today's gems.
The emerald is considered the most valuable member of the beryl family, and ranges in color from a pure green to a blue-green color. Its name comes from the Greek word "smaragdos" which translated means "green gemstone". A true emerald can be recognized by its jardin inclusions which are only evident in that particular gem. Exceptionally beautiful Columbian emeralds have the distinction of having jagged triple inclusions, and are often of a true green touched with blue.
Most people are not aware of the fact that this May birthstone goes through a six-step process to make it the emerald we know today: sawing, performing, cutting, polishing, cleaning, and enhancing. Emeralds not requiring clarity enhancement demand a very high price, and are usually accompanied by a laboratory report stating no enhancement was done. An oil (sometimes tinted) or resin treatment is usually a part of the process to fill cracks which can affect their endurance. Rings containing emeralds should always be removed before the wearer put his hands in water with a cleaning agent. This is because coatings which the cutter uses might be removed, giving the ring an unattractive matt finish. For the same reason, sonic jewelry cleaners should not be used.
Like the aquamarine, also in the beryl family, emerald crystals are hexagonal prisms. Pure beryl crystals are transparent, and the introduction of chromium and vanadium are what give it the green color. On the Mohl's scale it rates from 7.5 to 8 for hardness, whereas a diamond rates a 10. Cleopatra was said to have loved emeralds, but historians believe they were actually peridot.
Emerald synthetics can be quite easily manufactured, and also created from a combination of real and synthetic emeralds, so beware. If you purchase one be sure to have it examined by an expert to see if it is a natural stone or grown in a lab. A large emerald gemstone, depending on quality, can cost more than a diamond of the same carat weight. One of a vivid color can also bring more even with inclusions than a larger stone of paler color. Finding an emerald with both vivid color and fine transparency is rare.
The emerald is found in black limestone veins at Muzo, and at Chivor in Columbia as well as in Russia, Zimbabwe, Brazil, Madagascar, Pakistan, India, Afghanistan and Zambia. Seventy-five percent of Columbia's production comes from the Coscuez mine. The Columbian mines have also produced rare and eagerly-sought Traphice emeralds, which somewhat resemble a star sapphire, that is six rays emanating from a center.