Emerald is a green variety of beryl with its color having the richness and opulence of a blooming tropical forest.
A fine emerald is absolutely breathtaking; since antiquity, its color has been synonymous with the color green. Emerald is one of the four precious gemstones along with ruby, sapphire, and Paraiba.
The main sources are Colombia, Brazil, and Zambia, while Afghanistan, Ethiopia, Madagascar, Australia, Pakistan, and Russia have lesser deposits. The most famous emerald deposit is the Muzo mine, just northwest of Bogota, Colombia. There are several major emerald deposits In Brazil: Minas Gerais, Bahia, and Goias.
The colorless beryl is made of elements found in abundance close to the Earth’s surface. They are beryllium, aluminum, silicate, and oxygen. However, chromium which gives Colombian emeralds their insanely beautiful and desired color, is found 15 miles below the Earth’s crust.
Emeralds are the hardest stones to photograph; they are the most photoshopped gemstones. It is nearly impossible to take a picture that truly represents what you see in real life because digital cameras cannot capture the dynamic range of greens that exist in emeralds. The same problem affects the computer monitors as well.
Emeralds are photographed using macro lenses, visually flattening the image and combining all inclusions into a single plane. Oil-filled fissures invisible to the naked eye become visible on the photograph, creating an appearance of a heavily included stone.
A close-up picture of an emerald is not a fair representation of the stone’s true appearance, making a presentation of an emerald via picture or a video truly challenging.
Mohs Hardness: 7.5 to 8 out of 10
Color: Medium-light to dark green, slightly yellowish-green, and bluish green
RI: 1.577 to 1.583 (+/-0.017)
Birefringence: 0.005 to 0.009
Clarity Type: Type III
Optic Character: Uniaxial negative
Pleochroism: Moderate to strong green & bluish green
Spectrum: Broad absorption at 580 to 630nm. Lines at 646 & 662nm. Distinct lines at 680.5 & 683nm. Almost complete absorption of the violet.
Fluorescence: Generally inert. However, top colors may fluoresce orangy-red to red under LW & SW (stronger reaction under LW)
SG: 2.72 (+0.18 / -0.05)
Routine Treatments: Oil is a traditional treatment, generally accepted as natural.
Additional Enhancements: Excessive oiling, fracture filling, fracture filling combined with dye
Extremely rare top-quality Colombian emeralds command a higher per-carat price than diamonds. They are 400 times rarer than diamonds. But the green emeralds are not the rarest Beryl variety – that distinction goes to red beryl, called bixbite.
The historical values of Colombian emeralds demonstrate a continuous and uninterrupted increase in net worth of approximately 5-10% annually. Every year miners hunting for the gems in the elusive emerald-bearing veins have to dive deeper into the earth’s crust.
Emeralds have always been associated with royalty.
Emeralds were Cleopatra’s favorite gemstone. In 1845, Prince Albert commissioned an emerald tiara for Queen Victoria featuring 19 pear-shaped emeralds, the largest weighing 15 carats. In 1911 Queen Mary wore an emerald choker that would later be given to Princess Diana as a wedding gift from Queen Elizabeth.
John F Kennedy picked a Van Cleef & Arpels emerald engagement ring to propose to Jacqueline Bouvier in 1953. In 2011 Elizabeth Taylor’s emerald necklace was sold for $6.5 million at auction.
The bluish-green to pure green emeralds in medium to slightly dark tones are the most desirable. The strength, intensity, and even distribution of color are more important than the tone. The best emeralds have vivid saturation and high transparency.
Emeralds are type II gemstones, so inclusions are expected and are part of the crystal structure. Emerald’s inclusions do not diminish its beauty unless they are overwhelming and affect its appearance. Fewer visible inclusions make the stone more valuable however pure emeralds are practically non-existent. heavily included emeralds look cloudy and void of any brilliance.
Areas of discoloration indicate potential crumbling of the surface. Emeralds with surface cracks extending more than a third of the stone’s length are vulnerable and prone to disintegration.
The choice of setting depends on whether it is a ring, earrings, or necklace. Wearing an emerald in a ring is more likely to damage the precious gemstone.
A halo or a cluster of diamonds surrounding an emerald will absorb the hard knocks and protect the stone.
An emerald can be set in a bezel that wraps its girdle for better protection. Setting an emerald in a bezel is riskier than using prongs.
Also, bezel-set stones are harder to clean or unset for repolishing without destroying the mounting. Claw prongs provide sufficient protection for emeralds.
V-prongs do not offer any advantage when setting emeralds. It’s the opposite – setting the emerald tip into a V-prong carries more risk.
An emerald’s color often improves when it is set in yellow gold. Top-color stones are always set in platinum.
When setting rare and expensive emeralds, soft metals like 22K gold and pure platinum are used to make prongs.
Losing an emerald is bad luck. According to William Thomas Fernie’s 1907 book, “Precious stones for curative wear and other remedial uses likewise the nobler metals.” – “The falling of an emerald from its setting has been held an ill omen to the wearer, even in modern times.”
So choose your jeweler wisely!
Emeralds are cleaned by gently brushing with a soft-bristled toothbrush in warm, soapy water. Do not soak emeralds in any cleaning solutions, and never use an ultrasonic cleaner. If necessary, an emerald can be re-oiled.
Bixbite is an extremely rare and gorgeous variety of red-colored beryl. For every 150,000 gem-quality diamonds, only one red beryl is found. Gem connoisseurs love it, and it is marketed as Red Emerald.
Sometimes raspberry-colored beryl from Madagascar called Pezzottaite or “Raspberyl” is passed on as bixbite. Pezzottaite is also very rare but less valuable than bixbite.
Emeralds differ from inexpensive green beryl by their deep green color and intense saturation.
Emeralds and green beryls are the same species, along with aquamarine, heliodor, morganite, and bixbite. Pure colorless beryl is called Goshenite. The impurities cause various colors in beryl. Chromium and vanadium are responsible for the green color in emeralds, iron in blue aquamarines and golden beryls, and manganese in pink morganite and red bixbite.
Beryl crystals formed in hydrothermal veins from mineral solutions contaminated with impurities responsible for various beryl colors. Beryl is a cyclosilicate with the chemical composition Be3Al2 (SiO3)6.
Clear emerald crystals are highly prized among collectors and connoisseurs. Unfortunately, an emerald without visible inclusions that have not been treated with oil is a rarity. For centuries people used natural oil to infuse emeralds to conceal inclusions.
Oil is the most accepted emerald treatment. When used in small quantities, it has a minor effect on the stone price.
Using oil to fill fractures and cavities doesn’t change color. Oiling does not permanently alter an emerald’s look and can be removed or evaporated over time.
Laboratories grade the presence of oil in emeralds as none, insignificant, minor, moderate, or significant. It is recommended to recertify an emerald at the time of the purchase to detect an oil treatment applied after a no-oil certificate was issued.
Trapiches are emeralds formed by inclusions separated into growth sectors radiating in a star-like fashion from the crystal’s core. The name trapiche comes from trapiche (de azúcar) meaning “sugar. Their spikes look like the grinding wheels used to process sugarcane in South America.
Emeralds’ internal features such as veils and wisps of natural imperfections have been romantically termed “jardin,” since they appear like an overgrown, verdant garden. Unlike with diamonds, where clarity is essential to the stone’s value, inclusions are expected in emeralds. The inclusions are formed by gases and other minerals trapped inside an emerald crystal during the crystallization process. Inclusions are often viewed as desirable features aiding in emerald identification.
Egyptians were already mining emeralds as early as 3500 BC. It was one of the four precious stones God gave to King Solomon, according to the Bible. Egypt was the only source until the 16th century when the conquest of South America by the murderous Spanish conquistadors led to emerald’s discovery in modern-day Colombia.
Emerald is a May birthstone, but it is also a Zodiac stone for people born between June 21st and July 22nd.
According to Indian folklore, the word emerald is derived from Sanskrit Marakata, meaning “the green of things that grow,” and the Persian word Smaragdus which means “green stone.” The Incas thought that emeralds foretell the future and reveal truth.
Emeralds are hard but less tough than other gemstones. Their hardness of 7.5 to 8 on the Mohs scale is substantial. Unfortunately, emeralds contain a lot of minor fractures and inclusions, making them susceptible to cracking if knocked against a hard surface or subjected to extreme temperature change. Heavily included emeralds can be brittle.
Colombian Emeralds are the standard against which all other emeralds are usually compared. They are legendary for their deep color with just the right amount of blue and yellow. Colombian emeralds command higher prices than emeralds from any other localities.
Colombian emeralds were created millions of years ago during the formation of the Andes Mountains. The mineral-rich water seeping through the cracks between rock layers solidified into emerald-bearing veins.
Three primary mines have been operating in Colombia since the 1500s. The most famous is the Muzo mine, known to produce the finest, most prized emeralds in the world. The other two mines are Chivor, producing lighter, slightly more blueish material, and the Coscuez, with its warmer shade stones.
The other country producing fine quality emeralds in South America is Brazil.
African countries such as Nigeria, Zimbabwe, Madagascar, and Zambia all have emerald deposits, producing fairly decent stones but not ones as valuable as their Colombian equivalents. Zambia is the best source of African emeralds, where large deposits were discovered in the mid-1900s. African stones are darker and more bluish than South American emeralds.
High-quality emerald deposits were recently found in Ethiopia. The stones seemed to be clearer and more color-saturated than the Zambian emeralds. Although African emeralds are less fractured, they are still routinely treated with oil.
Colombian emeralds are mined in the area known as the ‘Emerald Belt’ of the Cordillera Oriental in the Gobernación de Boyacá and Cundinamarca district. There are three main emerald mining areas: Muzo, Coscuez, and Chivor.
This color is typically a vivid green. A butterfly (mariposa in Spanish) lives only in the Muzo area and has the same color. Muzo crystals do not form clusters or aggregates. They tend to be shorter than those from Chivor.
Coscuez crystals frequently occur as aggregates with multiple terminations. The crystals from Coscuez are longer than those from Muzo but shorter than those from Chivor. They have good transparency with a bright yellowish-green color but cannot be traced to the Coscuez mine by color alone. The inclusions are typically diffused and poorly defined.
Chivor emeralds are famous for their color and brilliance, even in dim light. Crystals from Chivor are elongated and do not form clusters or aggregates. They generally have a lighter bluish-green color and fewer inclusions. They have three-phase inclusions containing gas, fluid, and crystals of halite, pyrite, and albite.
In L. Frank Baum’s book, published in 1900, all residents of the Emerald City were duped into thinking that the city is built of emeralds. They were required to wear green sunglasses, which they apparently never took off. In the 1939 Wizard of Oz movie, the city was recast as a sparkling metropolis built entirely out of emeralds to take advantage of Technicolor.