Emerald Stone | Properties and Meaning
1. Emerald Green Variety of Beryl
2. Grading of Emerald Stones
3. Article Photos
4. Our Collection of Emerald Stones
Emerald Green Variety of Beryl
Emerald which is a distinctive, highly sought after and valuable gemstone is the green variety of the mineral beryl. Its unmistakable colour is caused by trace amounts of chromium and the chemical element vanadium. Flawless stones are incredibly rare and the vast majority are small, heavily included and feature surface reaching fissures and fractures which often cause stones to break easily. For this reason many are treated in order to fill cracks and to improve clarity. Numerous treatments have been devised over the years in order to hide or disguise flaws and the finest grade emeralds can command staggering prices.
Although commercial grade emeralds are available worldwide in abundance, fine grade stones are extremely rare. The history of this grass green coloured gemstone can be traced back to Ancient Egypt and is known to have been mined as early as 1500 BC. The name emerald comes from the Latin esmaralda/esmaraldus which was a variant of the Latin word smaragdus which originated in Ancient Greece. Smaragdos means green gem. Cleopatra loved emeralds and often covered herself in them during official occasions. Her palaces are believed to have been decorated with stones and having stated they were only fitting for Egyptian royalty, the emerald mines were made her personal possession. Her portrait was often engraved into larger stones which were then gifted to her favourite ambassadors.
National History Museum Los Angeles
Columbia mines more emeralds than any other country and most of the world's finest gemstones come from mines around Muzo which is known as the emerald capital of the world. The next largest producer is Zambia and a 5,655 carat emerald was found in October 2018 at Kagem which is the world's largest emerald mine.
Being lighter in weight than diamond and sapphire means that an emerald stone of the equivalent weight would be considerably larger. On Mohs scale of mineral hardness emerald stones grade 7½ to 8 quite hard but it's also brittle so will break easily. During the Spanish conquest of Peru the invading Spaniards tested stones by means of grinding and pounding hence thousands of emeralds were destroyed because they were deemed worthless simply for being too soft.
National History Museum Los Angeles
Grading of Emerald Stones
Several characteristics are taken into consideration when grading coloured gemstones but colour is generally the most important. Having said that with emeralds clarity comes a close second followed by richness of colour, saturation and tone. Despite being the green variety of the mineral beryl not all green coloured beryl is classified as emerald. In order to qualify gemstones undergo rigorous testing during which cut, shade and depth of colour, clarity and carat weight is assessed. Another interesting fact is that when assessing the clarity of a diamond, a loupe which is small powerful magnifier is used but when inspecting emerald stones it's generally done with the naked eye and if no visible inclusions can be seen, it will be classified as flawless.
The photos in this article are clickable and redirect to the original photographs. The exhibit at the top of the page is on display in the Smithsonian Museum of Natural History, Washington D.C. The second two are in the Natural History Museum Los Angeles. Both are courtesy of Stan Celestian.
Our Collection of Emerald Stones