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Emerald is the green gemstone variety of the mineral Beryl (the blue variety of the mineral Beryl is Aquamarine). Beryl is beryllium aluminum silicate, with the known chemical composition of Be3Al2Si6O18. Emerald crystals are hexagonal in nature. Large Emerald deposits are currently mined in Colombia, Brazil, and Zambia. Emeralds are mined throughout the world (Pakistan, Afghanistan, Russia, Australia, United States) but these are the three major sources. The Zambian and Brazilian Emeralds may be colored due to the presence of vanadium, whereas Colombian Emeralds usually achieve their coloration from the presence of chromium. Emeralds have been treasured as adornments in the form of jewelry for centuries. Emeralds are at least twenty times more rare than diamonds, but in the finest grades sell for approximately the same per-carat price as diamonds. Emeralds are readily available in lesser grades and even very large sizes, but are exceedingly rare in fine grades in any size. Widely recognized as the Birthstone for May and Astrological affiliation with Cancer (June 22 – July 22), Emerald is also the celebrated gemstone of choice for 20th and 35th Wedding Anniversary. The Emerald continues to be one of the most popular of precious gemstones, rivaling Diamonds, Rubies and Sapphires.
The principal Emerald deposits are currently mined in Colombia, Brazil, and Zambia. Emeralds are mined throughout the world (Pakistan, Afghanistan, Russia, Australia, United States) but these are the three major sources. Colombia arguably produces the finest Emeralds. As a general rule, Brazilian Emeralds tend to be darker in tone and more heavily included. The inclusions present in Brazilian Emeralds may be dark inclusions, where the light colored inclusions typically present in Colombian Emeralds (known as jardin) are considered to be less of a factor in adversely impacting the value. Zambian Emeralds tend to have more of a bluish cast than either Colombian or Brazilian Emeralds, and tend towards a slight grayish cast, which is not present in either Colombian or Brazilian Emeralds. The Zambian and Brazilian Emeralds may also be colored due to the presence of vanadium, whereas Colombian Emeralds usually achieve their coloration from the presence of chromium. Chivor and Muzo are the two major mining districts in Colombia. Chivor, northeast of Bogota, is in a very rugged terrain with thick forest vegetation. The two major mines of the district are Chivor and Gachala. In this area, the rock is primarily shale and sandstone. Emerald crystals can be found in veins containing pyrite, quartz, and albite. Muzo is the most famous mining district in Colombia. It is located 60 miles north of Bogota. The climate is hot and humid with relentless rainfall. Muzo, Cosquez, and Pena Blanca are the major mines. Emerald crystals can be found in calcite deposits in shale. Most of the Emeralds we offer are of Colombian origin, as these tend to have the most widely accepted popularity and represent the best value for our Customers.
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The usual factors that determine the value of all colored gemstones are clarity, cut, color and carat weight. In the case of Emeralds, color and clarity dominate value determination. All Emeralds have inclusions. These inclusions are characteristics unique to the formation of Emeralds (and some other Beryl varieties) and actually aid in identification of natural Emeralds and separation from created (or synthetic) Emeralds. These include faceted pyrite crystals, calcite jardin (or garden), spindle shaped cavities, and three phase inclusions with gas bubbles contained in microscopic liquid-filled cavities within the crystal, indicative of hydrothermal formation associated with Colombian Emeralds. Unlike other gemstones, these characteristic inclusions do not detract appreciably from the value of the Emeralds unless they are distracting or adversely impact the brilliance of the gemstone. Inclusions that are prevalent to the extent that they are distracting and diminish the brilliance of the Emerald will greatly reduce the value of the gemstone. Which color is the optimum color for Emerald is widely debated, but it can be stated that the more intense the color, the greater the value. In Colombian Emeralds, "Muzo Green" is a term used to define leaf-green colors associated with Emeralds mined in the location of the Muzo mines. Emeralds mined in the Chivor region in Colombia tend to have bluish secondary undertones, similar to those of Zambian origin. The color hue in Emeralds gives a clue as to origin, but cannot be the definitive test as far as origin, as Emerald hues from these three sources (as well as Brazil) can vary widely within each location. The key to the effect of color on Emerald valuations is color purity and intensity, regardless of source location. Cut and carat weight have a decidedly secondary effect on Emerald values. Very large faceted Emeralds, in excess of ten carats, are quite readily available if one is willing to settle for lighter tones, less intense color or reduced brilliance. The same cannot be said for Diamonds, Rubies and Sapphires. However, very fine grades of Emerald over one carat are very rare and with respect to value may rival and sometimes exceed that of Diamonds of equal carat weight and grading.
Since subtle differences in quality can make large differences in beauty (and price), it is important to select your jewelry from a professional who can guide you honestly and ethically in your purchase.
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