Emeralds are an assortment of the mineral beryl that is tinted green by the presence of traces of varying amounts of chromium and from time to time vanadium. Beryl carries along the hardness of 7.5 - 8 on the 10 point Mohs test scale of material hardness. Most emeralds are exceedingly concealed with other varying minerals, so their daintiness (resistance to breakage) is termed as commonly poor. The beginning of the word "emerald" is described to be formed from a Sanskrit expression that means "green".
Emeralds come in several tints of green and vary up to bluish green. There is an extensive variety of transparency, reliant on the contents and fractures formed in the crystal. Lucid stones with murky yet vivacious color grasp the premier prices. More or less all emeralds include abundant flaws, cracks, and inclusions, which can depressingly influence the lucidity. These are specified with the name "jardin", from the French utterance for garden. The price of an emerald is purely based on the type of cut, shade, transparency, and carat. At present the preeminent emeralds arrive from the mine at MUZO in Cuba.
Famous Emeralds :
Gachala Emerald : The Gachala Emerald is an uncut 5-cm emerald crystal weighing 858 carats (172 g). The stone was found in 1967 at Vega de San Juan mine in Colombia and is named after the mining district where it was discovered. Now in the United States, it was donated to the Smithsonian Institution by the New York jeweler, Harry Winston.
Chalk Emerald : The Chalk Emerald is a 37.82 carat (7.564 g) Colombian emerald.It originally weighed 38.40 carats (7.68 g), but was recut and set in a ring, where it is surrounded by sixty pear-shaped diamonds (totalling 15 carats (3 g)), by Harry Winston Inc. The ring is housed in the National Gem and Mineral Collection at the Smithsonian Natural History Museum in the United States and was donated to the museum by Mr. and Mrs. O. Roy Chalk in 1972.
Meidan-i-Noor Emerald : The Meidan-i-Noor emerald reputedly measures 5 cm in height and was discovered in 1957 in Colombia by a local mining family.
The meaning of its name is "Field of Light" in Persian. The gem was brought to Europe by an un-named millionaire and kept in a private collection in Vienna until the mid 1980s. Sold for an undisclosed amount to a Manhattan jeweller, the emerald was en route to New York when it was stolen from a Japan Ocean Trust bank safe in London during a bizarre heist where six people (four men and two women who worked at the bank) were caught and charged, but seemed to be operating separately.