There is evidence that emeralds were sold in Babylonian markets over years ago. In Greek mythology, Hermes gave a giant emerald as a gift for Aphrodite and in the Hebrew tradition an emerald was one of the four precious stones given to Solomon. One of the most famous collections of gems, including emeralds, was owned by the Ancient Egyptian queen, Cleopatra, over years ago.
Cleopatra owned the emerald mines of Egypt which were taken over by the Romans after her death. The Romans continued to mine for emeralds until the sixth century AD. The Egyptians also believed the gems could cure eye diseases and that the green colour of emeralds represented fertility and rebirth. For that reason, emeralds were placed at the throat of a mummy for protection during the journey into the underworld and to ensure the deceased person would have strength when they were reborn in the afterlife.
In India, emeralds were revered so much that they were inscribed with sacred text and worn as talismans by the elite, including Shah Jahan, builder of the Taj Mahal. In the mids, the Spanish forcefully took over several of the larger mines in Columbia, including the largest producing mine, Muzo, from local tribes. They enslaved and killed many of the locals in the process. In , divers recovered Columbian emeralds from a Spanish galleon that had sunk in Emeralds from the Muzo mine, Columbia.
Muzo mine in Columbia is still known for having a murderous reputation. Crime related to emeralds from the mine, was prevalent during the s and s. The esmeraldos , or emerald bandits, who live in the hillsides around the mine, were often involved. The kg Bahia Emerald has also been the centre of international controversy. It was discovered in Brazil in and is comprised of 9 crystals ranging in size from 22 cm to 3. It was moved to USA and eventually seized by Los Angeles detectives in after a gem dealer reported it stolen.
The emerald is now locked away due to ongoing disputes over ownership. There were nine men, one woman and three corporations that claimed to own the emerald. In addition, the government of Brazil claimed that the stone was mined illegally and should be returned. Beryl is the mineral that emerald is created from. Beryllium, aluminum, silicon and oxygen come together to create the mineral Beryl.
The right temperature and pressure conditions can be the start of forming emerald. Beryl is typically found in metamorphic rocks and in volcanic deposits or in fractures and cracks in large areas of granite rock. The presence of chromium in beryl is what generate the green color. The chromium that is retained in the lattice structure of the beryl absorbs different colors and reflects a vivid green. Trace amounts of iron can also impart a yellowish green color to the emerald.
Stones that do not have a richly saturated green color are not considered to be emeralds. All members of the Beryl family are aluminum beryllium silicates with a hardness of 7. The broad spectrum of Emerald greens, ranging from pastel to deep green with blue, brown and yellow tints, is created by trace amounts of chromium, vanadium and iron. The four criteria most important when choosing Emeralds are purity of colour, transparency, clarity and brilliance brightness.
As with most gems, colour is the most important factor. A little bit of yellow typically up to 15 percent can enhance a pure green, balancing its colour in incandescent light, while a little bit of blue brings depth, richness and warmth.
Transparency and clarity are best described as two different, albeit related, things in Emerald. In general, a transparent 'lively' Emerald with a few bigger visible inclusions will be valued higher. The first synthetic emeralds were produced in the mids, but it was not until the s that Carroll Chatham began producing synthetic emerald in commercial quantities. Once commercial production began, a steady supply of synthetic emeralds began entering the market.
Synthetic emeralds, also known as lab-created emeralds, have the same chemical composition and crystal structure as natural emeralds. They are sold beside natural emeralds in most mall jewelry stores in the United States. When compared to natural emeralds, the synthetics typically have superior clarity and a more uniform appearance than natural stones of equivalent cost. There is nothing wrong with synthetic emeralds, or synthetic stones of any kind - as long as their synthetic origin is clearly disclosed to the buyer.
They are simply another option for the buyer. Many consumers purchase synthetic emeralds and enjoy them because they obtain superior appearance at a substantially lower cost. The two key tests for separating natural emeralds from synthetic emeralds are refractive index and magnification. Natural emeralds generally have a refractive index that is slightly higher than most hydrothermally produced synthetic emeralds and much higher than most flux-grown synthetic emeralds.
These differences are not large enough to be relied upon for important determinations; however, they can serve as a valuable indicator. Magnification is the most important tool for separation of natural emeralds from synthetic emeralds. Synthetic emeralds can often be identified because they contain visible characteristics that are a product of the techniques used to create them. Hydrothermal synthetic emeralds might display characteristics that include: chevron-type growth zoning, nail-head spicules, and small gold inclusions.
Flux-grown synthetic emeralds might display characteristics that include: wispy veil inclusions, tiny platinum crystals, or parallel growth planes.
Many gemologists can quickly identify most synthetic emeralds by microscopic examination. Green gemstones: A collection of green faceted stones of various types.
Most of them are not emerald. If you want a green gemstone, which one would you choose based upon color and appearance? Beginning in the back row at left - the name of the stone and its locality, carat weight, and the price that we paid: 1 chrome diopside from Russia, 1. Notice how some of the least expensive stones are free of eye-visible fractures and obvious inclusions, while costly emeralds have fractures and inclusions that are clearly visible with the unaided eye.
Some people have such a high desire for "emerald" that they are willing to pay more for an emerald than for another green stone that is larger, cleaner, and more attractive. Buy what you like! They are often manufactured specifically to serve as substitutes. Green glass, synthetic green spinel, green cubic zirconia, and green yttrium aluminum garnet are common imitations used in place of emerald.
They might prefer to own an emerald, but they select the alternative stone instead because of its lower price or other characteristics. Chrome diopside and chrome tourmaline are deep green gems that some people purchase when they want a green gem. Tsavorite garnet is another gem with a wonderful green color. Dyed quartz can be a beautiful stone at a very low cost. Several examples of alternative stones and synthetic emerald are shown in the nearby photo.
The best rule for buying gemstones is: "Buy what you like! Home » Gemstones » Emerald Emerald The bright green gem of the beryl mineral family and May birthstone.
Author: Hobart M. Physical Properties of Emerald Color A distinctly green color that ranges between bluish green and slightly yellowish green. Stones with a light tone or a low saturation should be called "green beryl" instead of emerald.
Clarity Almost every natural emerald has eye-visible characteristics that can be inclusions, surface-reaching fractures, or healed fractures. Treatments to fill the fractures with oils, waxes, polymers, flux and other materials to reduce their visibility has been common practice for hundreds of years.
Luster Vitreous Diaphaneity Transparent to translucent Cleavage One direction of imperfect cleavage Durability Emerald is very hard, but almost all specimens have inclusions and surface-reaching fractures that compromise their durability.
Mohs Hardness 7. Crystal System Hexagonal. Often as prismatic crystals.
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