Why are Emerald's So Valuable?
6.55ct Zambian Emerald with Insignificant Oil
Table of Contents
- What is an Emerald?
- Where do Emerald's come from?
- A Brief History of Emerald's
- What gives an Emerald its value?
Emerald is a vivid green-coloured Beryl found in sedimentary, metamorphic and igneous rocks. It is one of the four precious gemstones alongside diamonds, rubies and sapphires; It is 20 times rarer than diamonds and sapphires but slightly less rare than rubies. Emerald's distinct beauty and scarcity make it one of Earth's most luxurious and desirable precious gemstones, alongside being one of the most valuable.
1. What is an Emerald?
Emerald is a Beryllium Aluminium Silicate which grows in a hexagonal crystalline structure. The building block of emerald is silica, one of the most common substances found on planet Earth. Silica, an oxide of the element silicon, is closely related to carbon. In an emerald, silica combines with the oxides of two metals: aluminium and the other, an exceedingly rare metal known as glucinium or beryllium. Then traces of chromium or vanadium in the Beryl cause it to develop a green colour and gain the classification of an emerald.
Just as ruby and sapphire are the same mineral but with different colouring elements, emerald, aquamarine, goshenite, morganite, and heliodor are also the same mineral. The distinctions between the five varieties of Beryl are due to the trace elements that differentiate the colours. In emeralds, the trace colouring element is chromium (and vanadium), and it must have this present to be classed as an emerald.
Rough Emerald Specimen
Why does an Emerald have Inclusions?
The vast majority of emeralds have inclusions and internal flaws, and these imperfections are unique to each gemstone and add to their innate beauty. Inclusions are a part of the emerald structure and are formed as the crystalline structure grows under heat and pressure. Emerald crystals typically have indistinct surface markings, and the type of inclusions give a clue to the origin and are crucial in distinguishing natural emeralds from synthetic emeralds. Three-phase inclusions, a combination of liquid, solid, and vapour, are found in Colombian emeralds. Two-phase inclusions, a combination of liquid and vapour, are found in emeralds from India. Tremolite Inclusions are found in emeralds from Zimbabwe, and Mica flakes, pyrite and calcite are seen in emeralds from all localities.
Why is an Emerald Oiled?
The application of treatments to enhance the beauty of gemstones is almost as old as the discovery and appreciation of gemstones themselves. Records of the oiling of gem material go back to ancient Greece. The principle of oiling is that while air-filled fractures in gemstones are visually evident, a fracture filled with a transparent oil or some other suitable material will be much less visible. While the oiling changes only the clarity characteristics of the gemstone, the reduction in flaws will naturally intensify the colour of an Emerald as these cracks no longer block the passage of light. The detection of oil is identified under microscopic examination, revealing interference colours within the fractures of the emerald. When purchasing an Emerald, the most acceptable treatment that does not adversely affect the price is 'Minor Oil' —emeralds that have had no treatment or oil and of gem quality, with good clarity, command extraordinarily high prices.
Can an Emerald be Fake?
Emeralds can be lab-created. There are two different processes used to create the emerald crystal. The first is the Flux Melt Method, and the second is the Hydrothermal Growth Method.
Flux Melt Method to Lab Create an Emerald
Flux Melt utilises powered emerald and a chemical solution which dissolves the crystal powder. Heat is applied to the solution, mimicking how a natural emerald is formed. Over several months, the emerald crystal regrows, looking nearly identical to its earth-formed counterpart. The crystals grown using the flux method have inclusions that resemble natural emeralds, but they also contain inclusions which are exclusive to lab-grown emeralds.
Hydrothermal Growth to Lab Create an Emerald
The hydrothermal growth process mimics the natural growth of an emerald in a hydrothermal vein, where water, heat, and pressure contribute to crystal formation. In a lab, this involves creating a high-temperature, high-pressure environment with specialised equipment called an autoclave. A nutrient-rich solution containing the raw minerals needed to form emeralds is prepared. A seed crystal (a small, pre-existing emerald crystal) is placed in the growth chamber. The autoclave is divided into two zones: a hot zone and a cool zone. The mineral solution dissolves under extremely high pressure and temperature in the hot zone. As the nutrient-rich solution circulates to the cool zone, emerald crystals begin to grow on the seed crystal. This process is slow and controlled, taking several weeks or months, sometimes up to a year, to grow high-quality crystals. The result is a synthetic emerald that is chemically, optically, and physically identical to its natural counterpart.
How do I know an Emerald is Real?
Distinguishing lab-created emeralds from natural emeralds requires gemological testing that examines their inclusions, growth features, and physical/chemical properties. These testing methods allow gemologists to identify whether the emerald is natural or synthetic and, if synthetic, which method was used to create it. We advocate that you obtain a laboratory report from a reputable gem lab to verify whether the emerald is natural or lab-grown. This will give you peace of mind when investing in a high-value gemstone.
What is an Emerald Cut?
Although emerald is a harder gem on its surface, rating 7.5 on the Mohs hardness scale, it is not a structurally tough gemstone. Emerald is internally brittle and can be prone to fracture and chipping. For this reason, it is usually faceted into its signature 'Emerald Cut' for jewellery. An emerald cut is a faceted step cut that combines a rectangular shape with shortened corner facets, maximising the emerald's distinctive green colour. This classic gem cut helps to insulate the emerald from potential external and internal damage, ensuring structural durability in the long term.
Extraordinarily rare 2.44ct Swat Emerald from Pakistan.
2. Where do Emerald's Come From?
Colombian Emerald
The most famous emerald deposits are found in Colombia, notably the Muzo Mine, 100km northwest of Bogota. The Muzo mine, comprised of 5 mining shafts: Tequendama, Catedral, Volvere, Puerto Arturo and La Rampa, yields fine-quality emeralds of a warm, vivid green colour. The emerald-bearing soft rock is loosened, and the rough emerald crystal is picked out by hand.
Historically mined by the Incas, the Muzo deposit was abandoned and rediscovered in the 17th century by the Spanish Conquistadors. This rediscovery triggered a long conflict between the conquistadors and the Indigenous people of the land. 1819, Colombia gained its independence, but the mines stayed under the control of the English, French and Spanish. Today, the land is owned by the Colombian government. It is leased out to local mining companies, with the most significant company emphasising ethical environmental and social responsibility as part of their values. Emerald is one of Colombia's most important exports, bringing in over half the country's total export income.
Miner holding a rough emerald extracted from the Muzo Mine in Colombia
Zambian Emerald
Zambia is now the 2nd most significant source of Emeralds in recent history. Zambian Emeralds are renowned for their cooler, slightly bluish-green colour. The deposits for this extraordinary emerald rough were discovered in the 1920s in the copper belt near the Kafubu River in the Ndola Rural Restricted Area. It was in the 1970s that serious commercial mining began in the region. The Zambian government is working to regulate mining practices to reduce issues such as illegal mining and forced labour. Gemfeilds, the largest and most sustainable mining company in Zambia, produces around 25% of the world's emerald supply and strongly emphasises ethical practices.
Panjshir Emerald
Panjshir Emeralds are from Afghanistan. There is evidence of the history of mining dating back to the Middle Ages, with both Threophrastus and Pliny the Elder referencing smaragdus from Bactria in their writings. The ancient Bactria region sits within the border of modern-day Afghanistan. The word smaragdus was used to describe a range of green gems, but to give weight to the theory of these being Panjshir Emeralds, oxygen isotope analysis of an Emerald from the Jewels of Nizams of Hyderabad, India, dating back to the late 18th century, concludes that the origin of the Emeralds is most likely from Panjshir Valley of Afghanistan. In modern times, the ongoing political unrest, accompanied by the harsh geological conditions of Afghanistan, means that fewer Panjshir Emeralds find their way onto the worldwide market, and for this reason, good quality examples are highly cherished.
Panjshir Valley, the origin of beautiful Panjshir Emeralds
Swat Emerald
Emerald, of Pakistani origin, comes from the Fizagat mine in the Mingora region of Swat Valley. Known as Zamurd to the locals, Swat Emerald has a history dating back 2500 years. Used by the Ancient Romans and in treasured antiquities of India, Swat Emeralds declined on the market as mining for them ceased. It was in 1958 that mining resumed, and Swat Emeralds reappeared in the modern gem market. Recently, several Swat Emeralds were evaluated by Gübelin, the most prestigious gem laboratory in the world, as being lively, with good transparency and colour saturation, rivalling Emeralds from the Muzo mine in Colombia.
Trapiche Emerald
A trapiche emerald is a rare and distinctive gemstone formed by a lutite impurity in the sedimentary rock. As the emerald forms, the black lutite is pushed towards the centre of the crystal, giving it a distinguished six-arm radial pattern. The value of a trapiche emerald is determined by the hue of green it presents, as well as the intensity of its black lutite black pattern.
Trapiche Emerald
3. A Brief History of Emerald
Emerald has a long and rich history, spanning back to the earliest writings known to humankind. Pliny the Elder stated in his early writings that the emerald stood in high estimation of the ancients. In the Bible, it is written that the rainbow is like unto an emerald. Nero and Domitian used Emeralds as ornaments for their dresses. Emeralds were excavated in Pompei and Herculaneum, and similar ornaments featuring Emerald were dug up from the ruins of Old Rome.
Archaeologists found Emerald talismans on the bodies and in the sarcophagus of Egyptian mummies, and it was discovered that the ancient Egyptians had mines near the Arabian Sea. These early mines were so large that 400 men could work together in them.
Isidorus, the Bishop of Seville (640 A.D.), said of the emerald that it surpasses in its greenness all green stones, and even the leaves of plants, and that it imparts to the air around it a green shimmer; that its colour is the most soothing to the eyes of those engaged in cutting and polishing the stone.
In the Manka Valley in Peru, there is folklore that the indigenous people, The Inca, paid homage to a magnificent Emerald the size of an ostrich egg, which they named the goddess of emeralds. The priests displayed it only during high festivals. When Peru fell to the Spaniards, many of the emeralds that the Inca people possessed were stolen. From this point onwards, emeralds become less rare in Europe, with jewellers and lapidaries preferring Peruvian stones.
Crown of Andes
The Crown of Andes
The Crown of the Andes is an extraordinary religious object featuring the oldest collection of Emeralds on a single artefact. Spanish artisans fashioned it in the 16th century in Popayan, which is present-day Colombia. When the conquistadors plundered the Inca's gold, they brought European diseases, and in 1590, a virulent strain of smallpox swept through the region. The faithful of Popayan prayed to the Virgin for deliverance, and miraculously, She spared them. In gratefulness, the congregation commissioned an extravagant crown for the statue of the Virgin Mary in their cathedral. The most antiquated parts of the crown are the orb and the cross at the top. Further gold and Emerald adornment were added year after year, with donations from the church. The centrepiece of the extraordinary crown is the Atahualpa Emerald, which was named after the last of the Inca emperor and reputedly seized after his defeat by the Spanish conquistador Francisco Pizarro. The crown was displayed yearly during the processions of Holy Week, but the word of its splendour soon spread. So, to protect it from thieves, the church set up a clandestine group of local nobles called the Confraternity of Immaculate Conception. At the first signs of strife, its members were entrusted with disassembling the crown and hiding the pieces throughout the jungle. The Confraternity kept the crown safe until 1936 when local clergy sold it to pay for a new hospital and orphanage. The buyers were a syndicate of gem dealers who planned to dismantle the crown and sell its jewels individually. However, it proved to be such a popular attraction that this decision was fortunately reversed. This significant piece of gemstone history is displayed intact at the Metropolitan Museum of Art in New York, USA.
The Topkapi Dagger
Another historically significant item featuring priceless Emeralds is The Topkapi dagger. This celebrated Emerald dagger is the star attraction of the Topkapi Palace Museum in Istanbul, Turkey. Topkapi is one of the finest objects of its kind, but its origins are linked with murder, bloodshed and treachery. Fashioned in Istanbul in the mid-18th century by the royal craftsmen of the Ottoman ruler Sultan Mahmud I, Topkapi was most likely commissioned as a diplomatic gift for the Persian leader Nadir Shah. Shah was known as "the Napolean of Persia" and was the most powerful military figure in the region. He had waged a bitter war against the Ottomans, but the two countries eventually made peace in 1746 and exchanged gifts. Mahmud's contribution included the spectacular dagger, an intelligent choice as Nadir's fondness for jewels was well known; he seized many during his campaigns in India, including the Koh-i-Noor diamond. The dagger is dominated by four enormous emeralds, and in the Islamic world, emeralds are highly prized and exotic. These particular Emeralds originate from the Muzo mine in Colombia. The large upper and lower Emeralds are pear-shaped, and the middle emerald is a rectangular cushion cut. A fourth Octagonal Emerald is set on top of the handle and lifts to reveal a watch. Diamonds, enamel and mother-of-pearl decoration are set into the gold of the handle and sheath. Unfortunately for Nadir Shah, he never lived to see the dagger, as while the gifts were in transit, he was assassinated in this bed. Upon news travelling, the escort party halted their journey and returned home, and the dagger was kept at the Topkapi Palace, where it is still on display today.
Emerald is the Birthstone for May
The modern concept of birthstones was established in 1912 by the then-National Association of Jewelers. Emerald was crowned the birthstone of May for its lush, verdant green hue, the colour that is a metaphor for spring, growth, and new beginnings. The concept of birthstones is woven into the fabric of our society, and birthstones are a popular choice for gem-lovers to celebrate their birthday or gift-givers to spoil a loved one on their birthday. For those born in the month of May, an emerald is the perfect adornment for you.
4. What gives an Emerald its value
How Does the Colour of an Emerald Affect its Pricing?
There is an exact science behind the colour grading of emeralds. Here at The Sapphire Merchant, we use World of Color, which is based on the Munsell Colour System. A single change in the shade of green has an impact on emerald pricing. Colour grading is from 1 - 10, 1 being the lowest colour grade and 10 being the highest colour grade.
Three dimensions of colour apply to the grading of coloured gemstones. These dimensions are hue, saturation and tone. Hue describes the colour we see when looking at a blue sapphire. The hue has to be a part of the colour wheel and, therefore, a derivative of primary colours. The second dimension of colour is the saturation. Saturation refers to the richness and vibrancy of the colour. Tone is the third dimension of colour. This is the lightness or darkness held within the gemstone and how it refracts its colour.
The Clarity of an Emerald
The clarity of an emerald relates to how translucent and clean the emerald appears to the unaided eye and under x10 magnification. An emerald with no internal inclusions and clear transparency is graded as internally flawless (IF) or slightly included. This clarity grade is an absolute rarity among emeralds known for their natural inclusions. Once inclusions become visible, the clarity grading will be classified as moderately included or heavily included. Factors affecting emeralds' clarity include colour zoning, needle-inclusions, mica, calcite and pyrite inclusions, and two-phase and three-phase inclusions. Light to moderate inclusions are normal in high-quality emeralds.
A Lab Report and Certification for an Emerald
Documentation is essential, as it ensures the authenticity of a natural gemstone. Emerald's can be lab-created, and to the untrained eye, it is hard to tell the difference between a natural earth-mined emerald and a laboratory-created synthetic emerald. Having accompanying documentation, such as a laboratory report, gives you confidence in the product you purchase. The Sapphire Merchant offers reports with all our emeralds, and upon request, we can upgrade any of our gems to a GIA report.
Buying and Emerald in New Zealand
The Sapphire Merchant is New Zealand's premier precious gemstone retailer and custom jewellery house. We travel to source and hand curate Earth's most exquisite precious gemstones. The Sapphire Merchant makes the exciting process of buying an emerald in New Zealand simple. We travel to the world's most distinguished gem markets and hand-curate our superb collection of emeralds. Peruse our sensational range and uncover the gemstone meant for you and only you! Whatever you can dream of, The Sapphire Merchant can design and create for you. Contact us today to start a journey that defines your moment with an incredible custom jewellery piece.