Emerald is most valued variety of beryl; occur in hues ranging from yellow-green to blue-green. Best quality Emerald is transparent and verdant green. Most emeralds are oiled to improve their clarity. The emerald is often clouded by inclusions, they are not classified as faults but show the difference between natural and synthetic stone.
Hardness of 7.5 – 8.
Emerald Treatments:-
Beware of coated beryl: look for peeled coating (surface-reflecting light) - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 6
Impregnation of the crystal faces with oil is used to conceal minute fractures and improve transparency. Canada balsam, cedar resin, kerosene and other similar materials may be used instead of oil. A technology was developed in Israel, in which fractures were filled with a melt of bismuth and lead under vacuum at high temperature to strengthen raw emerald prior to cutting. - E.Ya. Kievlenko, Geology of gems, 2003, p. 75
Significant Gem Localities:-
Emeralds is mined in countries such as Afghanistan, Australia, Austria, Brazil, Bulgaria, Cambodia, Canada, China, Egypt, Ethiopia, France, Germany, India, Colombia, Italy,Kazakhstan, Madagascar, Mozambique, Namibia, Nigeria, Norway, Pakistan, Russia, Somalia, South Africa, Spain, Switzerland, Tanzania, United States, Zambia, and Zimbabwe. Colombia and Zambia are the leading producers. Six-pointed radial pattern trapiche emeralds are found in Colombia .
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