The “Bahia Emerald” – one of the largest ever found – is an 850 pound (1,930,000 carat) Brazilian stone reported stolen in September 2008 from a secured vault in South El Monte in Los Angeles County, California, according to someone claiming to own the giant gemstone. While the stone had been appraised at $370 million the true value is unclear. At one point, the emerald was listed for sale on eBay for a “Buy It Now” price of $75 million.

On July 9, 2001, a miner in the Carnaiba emerald mine came upon the head of an unusually large crystal protruding from black rock. Within minutes, everyone gathered around to watch one of the veteran miners excavate the rock around the crystal using a small pick and hammer. Several hours later, they all stood around the most awesome concentration of Emerald crystals that anyone had ever seen.

Knowing that word of such a treasure could cause unwanted attention, the mine supervisor quickly assembled a team of his most trusted miners with the purpose of moving the rock containing the crystals to a safe place. It took eight men over five hours to move the 850-pound rock to the nearest clear trail. There they assembled a team of mules for a journey that would take them over 700 miles through unforgiving jungle and last almost 11 months.

Five months into their journey, their mules were attacked by a pair of black panthers. Having no other choice, the eight men built a stretcher from wood and vines and carried the rock by hand the rest of the way.

When the miners finally arrived in Sao Paulo on April 20, 2002, they brought the rock to the Bank of Brazil. A world renowned gemologist was brought in to appraise the find, and when he was finished, announced that it was indeed one of a kind. Fearing that the rock could fall into the wrong hands, it was immediately shipped to the United States under heavy guard so that it could be further examined by scientists and collectors.

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.

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.

Emeralds are a variety of the mineral beryl (Be3Al2(SiO3)6,) colored green by trace amounts of chromium and sometimes vanadium. Beryl has a hardness of 7.5 – 8 on the 10 point Mohs scale of mineral hardness. Most emeralds are highly included, so their brittleness (resistance to breakage) is classified as generally poor. The word “emerald” comes from Latin smaragdus, via Greek smaragdos, its original source being a Semitic word izmargad or the Sanskrit word, marakata, meaning “emerald” or “green”.

Color

Scientifically speaking, color is divided into three components; hue, saturation and tone. Yellow and blue, the hues found adjacent to green on the spectral color wheel, are the normal secondary hues found in emerald. Emeralds occur in a range of hues from yellowish green to bluish green. The primary hue must, of course, be green. Only gems that are medium to dark in tone are considered emerald. Light toned gems are known by the species name, green beryl. In addition the hue must be bright (vivid). Gray is the normal saturation modifier or mask found in emerald. A grayish green hue is a dull green hue. In the trade, a fine emerald will have a vivid primary green hue only slightly modified by yellow and/or blue with no visible gray mask.

Famous emeralds

• Gachala Emerald (origin: Colombia)
• Chalk Emerald (origin: Colombia)
• Bahia Emerald (origin: Brazil)