Of the varieties of the mineral beryl, emerald is the most valuable, and is usually considered to be the most precious of the “four precious” gemstones (diamond, ruby, sapphire). The unique color of emerald is made by traces of chromium and vanadium, and can range from medium to dark green to blue-green and yellowish green.
Though Columbia and Brazil are perhaps the most well known for mining emeralds, they are being mined all over the world in places like South Africa, Europe, and Russia to name a few. One of the reasons that emeralds can command such high prices is due to the nature of beryl, which is often heavily included with other minerals and nitrogen, and as a result is not as resistant to breakage. Emerald prices get very steep very fast the less included the stone is, as this not only increases its clarity, but structural integrity as well.
Due to the heavy inclusions that create fissures and cracks, most natural emeralds are often treated with oil or resin, usually on-site at the mine. While this colorless process fills in the gaps, it does not make the stone harder. Though emerald is a 7.5 to 8 on the Mohs scale, the stone behaves quite a bit softer due to its natural "included" condition. Interestingly, these natural inclusions are well-tolerated more in emeralds than other gemstones. An emerald’s inclusions not only validate that it is natural, but they’re also considered to add character to the stone.
When considering buying an emerald it is best to keep in mind that the most expensive emeralds will be more transparent than opaque. If you come across an emerald that seems very low priced and is crystal clear, it’s likely a synthetic lab-created stone. And while there are some advantages of a lab-created emerald like durability and color, man-made stones are still a far cry from what mother nature has taken billions of years to create. Below are a few of ours that we like...
Our friends at Navneet Gems & Minerals have been kind enough to allow us to use an emerald quality chart they developed, so you can see the various grades of polished emeralds available:
Thanks to the emeralds hardness, most higher gem-quality stones can be cut into a variety of shapes. The most popular, however, is still the gem’s namesake: the emerald-cut, which is a rectangular or square step-cut with truncated corners. The emerald-cut highlights the beauty and color of the stone, and reduces internal stresses.
Emerald is the birthstone for May, and the 20 and 35th wedding anniversary stone. Emeralds have been mined and sought after since at least 3000 BC! Thought to be ‘power’ stones, they have always adorned jewelry worn by the richest and most powerful people on Earth. Emeralds have been said to increase fortune and luck, and to promote healing. Whatever their ‘powers’, there is little doubt that they have caught the eye of men and women alike for centuries, and will continue to do so.
A little special care is needed when cleaning emeralds. The use of solvents, steam cleaners, and ultrasonic machines is not recommended because these can strip away oils that have been applied to the stone after it has been mined. There is also a risk that the heat from ultrasonic machines and steam cleaners could exacerbate cracks and fissures, potentially causing a stone to break. It should be noted, however, that if the oil from an emerald is stripped away, thus causing inclusions to become more visible, the oil can be reapplied to renew the original look of the stone.
To clean your emerald, simply apply a mild soap to a soft cloth and wash in warm water. Rinse and dry, and remember to store your emerald in a fabric lined jewelry box, or wrap in a soft cloth to keep scratches at bay. Please remember to remove any jewelry when using cleaning chemicals such as bleach!