Article title: Emeralds
Article main body:
Emerald called the green variety of beryllium.
The name emerald was used by ancient Greeks (Theophrastus) and meant the precious green stones. Possible origins of the word is the Sanskrit word samaraka or Persian zamarrad. In the West came as «esmeralde" to produce the current emerald.
The emerald knew and worshiped by many ancient civilizations. The earliest mines were in Egypt near the Red Sea, and mined for the Pharaoh in 3000 BC to 1500 BC Later it was known as "Cleopatra's Mines." The Incas and Aztecs of South America (where over time are the best quality emeralds), were used for religious purposes. In the Vedas, the scriptures of the Indians, the emerald is referred to as the stone of luck and good health, so take care of the Maharajas have always held the emeralds. One of these, the "Great Mongol" dates from 1695, weighs 217 carats, and is engraved on one side and prayers on the other side of a flower, was sold in 2001 by the auction house Christie's of London, at the price of $ 2.2 million .
Generally the famous emeralds held recovers, emperors and sultans are now in museums like the Museum of Natural History in New York, or the Topkapi Palace in Istanbul.
The Bible makes it like a stone that was removed when the devil was expelled from paradise. Herodotus refers to the emerald ring of Polycrates, and the emerald column of Hercules, and finally the Roman Pliny says that the Emperor Nero watched the fights, with an emerald lens.
The emerald has the chemical formula Be3Al2 (SiO3) 6Cr, and hardness of 7.5 - 8. The striking green color due to impurities Cr2O3 (chromium oxide). The admixture is conditional contributes to cracking the emeralds. Sometimes as an impurity in emerald contained vanadium. Emeralds today are produced in mines in Zimbabwe Sandawana. The emeralds are considered the oldest fossil of the planet 2600 million years old, Brazil mine Nova Era in India, Zambia, Pakistan and Madagascar. The world's leading and most expensive emeralds produced in Coscuez mine in Colombia, from 60 staff in conditions of maximum security.
The emeralds are usually cut into a rectangular cut that has the name "emerald cut", because it is believed that better highlight the color and shine. Often some emeralds contain inclusions, which is not always undesirable, because they give specific information on the origin of the stone and the identity and uniqueness. The imitations, synthetic, and artificial emeralds are treated much more in the real market.