Emerald is the green variety of the mineral beryl and one of the most highly prized of all the gems. Emerald was an enemy of all enchantments and conjurations. It was therefore greatly feared by magicians, who found all their arts of no avail if an Emerald were in their vicinity when they began to weave their spells. However those caught by Cupid's bow found the gemstone useful in learning the truth or falsehood behind the oaths of their lovers.
Today Brazil and Zambia produce large quantities of Emeralds; however, many still consider Colombian emeralds to be of the highest quality. Very fine emeralds, are also produced in Pakistan and Zimbabwe. Emeralds of Zimbabwean origin are sometimes called "Sandawana" Emeralds, which refers to the region where the gemstones are mined.
Emeralds are made of the base mineral Beryl, with minute traces of chromium and vanadium giving this gemstone the "green fire". Colombian Emeralds are known for their vivid green color, while Brazilian Emeralds are known for their variety of color, ranging from light green to fine medium dark green.
Legend: According to legend, the wearing of emerald not only cured a wide range of ailments, including low I.Q., and infertility, but also enabled the wearer to predict the future. As a revealer of truth, this gem was an enemy of all enchantments and conjurations. It was therefore greatly feared by magicians, who found all their arts of no avail if an Emerald were in their vicinity when they began to weave their spells. However those caught by Cupid's bow found the gemstone useful in learning the truth or falsehood behind the oaths of their lovers. The Emerald has also been worn or utilized in magic for protection. The stone was bound to the left arm with string to guard travelers. They were given to "possessed" persons to exorcise the evil entity within them. Emeralds were employed as an antidote for poisons and for poisoned wounds. To gaze into an Emerald was said to increase sight and relieve eye strain.
Colour: The finest quality emerald has the fresh young green grass colour, an almost pure spectral green, possibly with a very faint tint of blue, as in the "drop of oil" emerald from Colombia, which is considered to be the world's finest. Its fine intense green coloring is due to a trace of chromium or vanadium replacing the aluminum in the beryl structure. Because of the nature of this replacement, almost no Emeralds with intense color are free from inclusions.
Clarity and transparency are the most important characteristics of Emeralds. When evaluating from a face up position, very fine quality Emeralds should enable the viewer to see the back facet.
The brightness of the gemstone, which is determined by the cutting and the number of inclusions, is also an important evaluation factor. Intense medium green Emeralds command the highest value.
The purity of the green color is crucial to the value and the beauty of the stone, with blue or yellow overtones diminishing its value.
Hardness: With hardness close to 8 on the Moh's scale, Emerald is quite durable. However, ultrasonic and steam cleaning could damage the stone, causing fractures.
Treatment: All emeralds that are used for jewelry go through six-part enhancement process to become the gemstones we know. The steps are sawing, preforming, cutting, polishing, cleaning, and clarity enhancing. Virtually all emeralds require the process of clarity enhancement. This process involves immersing the emerald into a colorless medium. An infinitesimally small amount of the clarity-enhancing medium penetrates open fissures. It should be assumed that every emerald has been processed in this manner unless it has an accompanying laboratory report indicating that there is no evidence of a clarity enhancement medium. Such extraordinarily rare gems command a considerable premium.
Agents used for clarity enhancement are colorless or near colorless: oils (fair stability), prepolymers and uncatalyzed resins (fair to good stability), paraffin (good stability), and polymers (excellent stability). Using any of the above, except for polymers, to enhance an emerald produces good initial results, but there are some limitations to the effectiveness of these enhancements. Over time, the agents will escape the fissures in the emerald and again reveal the inclusions. Cleaning an emerald using traditional jewelry cleaning products and techniques will serve to remove these agents from the fissures. The emerald will need to be enhanced, occasionally by oiling, to maintain its beauty.
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