Emerald Treatment
Like most other gemstones, about 99% of all emeralds undergo treatments to improve their color, clarity, and sparkle. Since emeralds are so heavily included, they often need treatments to protect and/or repair naturally formed fractures in the stone, and these treatments can also intensify the emerald’s color. Untreated emeralds are extremely rare (about 1% of all emeralds) and generally cost about 10-20x more than treated emeralds if they’re high quality.
The standard emerald treatment is called oiling,where the stone is soaked in hot cedar oil. The hot oil soaks in and fills in any fractures, cracks, or fissures. Then, once cooled, the cedar oil solidifies and results in better clarity, a more vivid color, extra sparkle, and a more structurally sound stone.
Less common treatments include dyeing, lasering, and irradiating. Any emerald treatments should be disclosed to the buyer.