Emerald - Information and Emerald Jewellery Buyers Guide

Learn about emerald gemstones and buy emerald jewellery from a reputable shop

 

Emerald

Emeralds are known for their rich green hue, which can vary from light to dark shades. The intensity of the green colour is determined by the presence of trace amounts of chromium and vanadium in the crystal lattice of the gemstone. These elements are responsible for the captivating green colour that emeralds are famous for.  

Fine quality emeralds are found in Brazil, Zambia and Colombia along with quite a few other countries across the globe.  Chemically, emeralds belong to the beryl mineral family and beryl can be found in other colours.

Ancient civilizations were among the first to recognize the allure of emeralds. The Egyptians, believed that emeralds symbolized fertility and rebirth. Cleopatra, the legendary Egyptian queen, was particularly fond of emeralds and often adorned herself with these exquisite gemstones.

The allure of emeralds spread across different cultures and time periods. In ancient Rome, emeralds were associated with Venus, the goddess of love and beauty. Roman emperors and nobles wore emerald jewellery as a symbol of status and power

Click here to see our current stock of emerald jewellery



The Formation of Natural Emerald:

The formation of emeralds begins deep within the Earth's crust, where intense heat and pressure create the perfect conditions for their growth. The process starts with the interaction of hot fluids, rich in minerals. These fluids, often referred to as hydrothermal fluids, must contain a variety of elements and compounds that are essential for the formation of emeralds.

As the hydrothermal fluids move through the cracks and fractures in the rocks, they dissolve minerals and carry them along. When these fluids come into contact with the right combination of elements and conditions, emerald crystals begin to grow. The process is slow and can take millions of years to complete.

 

Emeralds in Jewellery

Emeralds are not as tough or as hard as diamonds, sapphires or rubies so need more careful treatment particularly when set in rings.  Emeralds are also commonly oil or resin treated - they often have small fissures and these treatments are used to stabilise the gem.  These treatments can be damaged by household cleaning products and bleach, so emerald jewellery should be removed when completing house work.  They are also susceptible to chips so emerald jewellery is best removed before diy or manual work.

If you have an ultrasonic cleaner for your jewellery you must not use it for your emerald pieces.  The nature of these stones makes them much more likely to crack or have stabilising treatments damaged than most other gems.  

If you are looking for emerald jewellery to wear everyday try selecting a piece where the mount gives protection to the stone, and also consider lab-grown stones which are more readily replaced for a more reasonable price if the worst happens.

 

Emerald Value

Colour of an emerald is the most important factor in determining its value. The finest emeralds exhibit a vivid, intense green colour with a slight bluish undertone. The colour should be evenly distributed throughout the gemstone, without any visible zoning or colour banding. The presence of other hues, such as yellow or brown, can significantly decrease the value of an emerald.

Clarity refers to the presence of inclusions or imperfections within an emerald. Unlike some other gems, emeralds are known for their natural inclusions, which are often referred to as "jardin" (French for garden) due to their resemblance to foliage. The most valuable emeralds have minimal inclusions that do not affect their transparency or overall beauty.  It is very uncommon to find totally clear emeralds and these fetch a large premium.

Cut - the 'cut' of a emerald in relation to quality depends on a number of factors much like for diamond.  Factors include the proportion, shape, and quality quality of surface polish

Carat - the carat of an emerald is simply it's weight with the unit being a 'carat'.  One carat is 200 milligrams metric weight and for gemmology and jewellery purposes a carat is also divided into 'points'.  One carat = 100 points, so a 50 point emerald is 1/2 carat for example.

If you can measure your emerald then you can use a mathematical formula to estimate its weight, although this is never quite perfect as slight differences in the facets and cut will skew the result.  If the emerald is not mounted in jewellery it can be weighed on specialist scales for a near perfect result.  When set in jewellery carat weights are estimated within the limits of accurate measurement.



Emerald Certification

Rubies can be tested and certified by specialist laboratories, perhaps the best well known being the GIA.  Gems are tested by specialists using advanced tools to certify their quality, their origin (natural or synthetic), and any treatments or enhancements they have received.

These tests are best done on unmounted stones before they are set into jewellery, and a certificate from a respected laboratory will increase the value of the gem.  However such testing is not cheap with prices currently around £120-250 ($150-300) for a comprehensive certification, more for higher carat weight stones.  While worthwhile for higher value pieces for general jewellery it is usually not done as it significantly increases the cost for little benefit to the consumer.

It is important to note that mounted emeralds cannot be tested to the same standard and only certain criteria can be checked, results will also be less accurate.  Also note that there are many labs (especially labs in India and China) which provide credit card type certificates with stones.  The value of these certificates is limited and cannot be relied upon for accuracy and they are sometimes more of a marketing exercise than an impartial test.

 

Emerald Enhancements

Natural emeralds are often subjected to 'enhancements'.  These are usually designed to reduce visible flaws, improve the colour or stabilise faults.  Some of these techniques are difficult to detect in the secondary market without advanced (and expensive) tests.  A GIA certification should reveal such treatments but will lead to a significant increase in price for the item.

Common enhancements include:

Oiling: One of the most widely used methods for enhancing emeralds is oil treatment. This process involves filling the fractures and imperfections in the gemstone with a colourless oil, such as cedar oil or mineral oil. The oil fills in the gaps, improving the clarity and overall appearance of the emerald. This treatment is considered standard practice in the industry and is widely accepted.

Resin Bonding:  Resin treatments are another popular method for enhancing emeralds. In this process, a clear resin is used to fill the fractures and enhance the colour and strength of the gemstone. The resin provides stability and improves the overall appearance of the emerald. It is important to note that resin treatments may require periodic reapplication to maintain their effectiveness.

Heating: Heat treatments are commonly used to enhance the color and clarity of emeralds. By subjecting the gemstone to controlled heating, the natural impurities and inclusions are altered or reduced, resulting in a more vibrant and visually appealing emerald.

 

Lab Grown (Synthetic) Emeralds

Lab grown emeralds were developed in the 1930's but didn't appear on the market until the 1940's and were still of limited production well in the 1960s.  A new process in the 1960's helped increase the market available quantity and quality, but production still lags significantly behind lab grown ruby and sapphire.  They are also more expensive to produce than rubies or sapphires.

Synthetic emeralds are created in a laboratory using advanced technology and scientific processes. These processes are made to mimic the natural formation of emeralds, resulting in gemstones that are visually indistinguishable from their natural counterparts although they are generally of a higher clarity and better quality than most commercial jewellery natural emeralds.

One of the key advantages of synthetic emeralds is their affordability. Natural emeralds of high quality are rare and command high prices due to their limited supply and the challenges involved in their extraction. On the other hand, synthetic emeralds can be produced in larger quantities, making them more accessible to a wider range of consumers.

Despite being man-made, synthetic emeralds possess the same physical and chemical properties as natural emeralds. They exhibit the characteristic green colour that emeralds are known for, ranging from a vibrant grass green to a deep forest green. The colour is created by introducing trace amounts of chromium and vanadium during the synthesis process.

Another advantage of synthetic emeralds is their superior clarity. Natural emeralds often contain inclusions and imperfections, which can affect their overall appearance. In contrast, synthetic emeralds are created under controlled conditions, resulting in gemstones with exceptional clarity and transparency.

When it comes to durability, synthetic emeralds are usually more resilient than there natural counterparts. This is due to them having fewer natural flaws and inclusions. However, it is important to note that all emeralds, including synthetic emeralds, should be treated with care to ensure their longevity.

 

Emerald Simulants

Simulated emeralds are not genuine emeralds, but alternative gems which have a similar look.  They can be man made or natural, but they will not test as emerald and may have a lower value.

Natural simulants include:

  • Tsavorite Garnet
  • Chrome Diopside
  • Green Tourmaline

Common man made simulants include

  • Lab grown spinel
  • Soude emeralds (doublets)
  • High dispersion glass (eg Swarovski Crystal)
  • Cubic Zirconia (CZ)

As long as you understand what you are purchasing there is no problem with buying jewellery with lab grown or simulated rubies at the appropriate price.