With a name said to be derived from the Sanskrit term Marakata, which means – the green of growing things – emeralds have fascinated the world for over six thousand years. There is evidence to indicate this green gem was sold in markets in Babylon as far back as 4000 BC.
A much sought-after gem, the emerald symbolises beauty, status and power and is coveted particularly for its rich color. The Greek philosopher Aristotle was said to be a huge fan of this green gem and believed it enhanced the owner’s social and business standing, improved eyesight and prevented the onset of diseases like epilepsy.
Emeralds are gemstones from the beryl family. Often described as a deep-green stone that is harder than quartz, but softer than a sapphire, ruby or a diamond, the best quality emeralds are mined high up in the Andes mountain range of Columbia, though other countries including Zambia, Brazil and Zimbabwe also produce significant quantities of emeralds.
As with most colored stones, it takes a trained eye to recognise the subtle quality variations that decide the true value of an emerald, more so in the case of the highest quality stones.
Here are some important pointers that can help you choose the right high-quality emeralds before you decide to buy them.
The best quality stones often vary in colour from a bluish green to deep green and are highly transparent. For example, Columbian emeralds exhibit a more intense green colour while those from Zambia are more bluish green. These fluctuations in colour are caused by the presence of trace elements like iron, vanadium and chromium in varying degree.
USEFUL TIP: If the colour of the stone betrays a yellowish or intense blue hue, it may not be an emerald but a different kind of beryl with a lower value.
High quality emeralds are known to contain certain inclusions called jardin (French for garden) that are often visible to the naked eye. For example, three-phase inclusions found in some high quality emeralds from Columbia are known to contain tiny crystals of liquid, rock salt and a bubble of gas. Gems without any inclusions are extremely rare and are considered to be very valuable.
USEFUL TIP: Small inclusions in an emerald are acceptable because they make an emerald unique. However too many can cloud the gem’s transparency and clarity lowering its value proportionately.
Emeralds tend to be brittle stones and hence the way they are cut assumes added significance. Cutting a rough wrongly can result in a significant weight-loss reducing the gem’s final value substantially.
Experts cutters are known to execute cuts that minimise the effect of fractures (also referred to as fissures) found on an emerald’s surface. If done right, cuts offer credible protection from damage with the vulnerable spots being faceted.
Finely cut emeralds are also known to showcase better hue, tone and saturation. This is achieved by balancing the gem’s proportions with the number of facets.
USEFUL TIP: A master cutter can easily darken a pale rough with a deep cut and lesser facets or make a darker rough lighter with a shallow cut and more facets.
A well-cut emerald can weigh anything from a fraction of a carat to hundreds of carats like those in private collections or on display in museums.
A case in point here are the emeralds mined from Zimbabwe’s famed Sandawana mine. They are known for their vivid colours but seldom weigh over 1.50 carats, with a majority of the roughs averaging a miniscule 0.05-0.25 carats – the kind used for making jewellery. Custom made jewellery may include larger emeralds weighing well over 20 carats.
USEFUL TIP: The smallest size emeralds range between 1-5 mm, weighing between 0.02- 0.50 carat. Larger ones, between 1-5 carat are popular as centre stones.