Oiling is a standard industry practice for enhancing emeralds. Most, but not all, emeralds receive oil treatments. These gems may lose their oil over time or by accident. However, you can re-oil emeralds. This emerald-cut emerald received a traditional oil treatment. © Dan Stair Custom Gemstones. Used with permission.
Answer: Before you re-oil emeralds, make sure you have actually removed all the old oil. You can do this by slowly simmering — not boiling — the stone in soapy water. Soaking it in a solvent like alcohol will also do the trick.
Emeralds almost always have inclusions. Some oil treatments try to make an emerald’s jardin (or “garden”) of inclusions more visually pleasing. Oil treatments are also used to enhance color. Emerald ring, photo by Mauro Cateb. Licensed under CC By 2.0
To re-oil emeralds, all you need to do is submerge the stone in an appropriate solution (oil, epoxy, etc). Next, place the stone and the solution somewhere warm. The back of a stove or a sunny window in summer are great locations. Keep it at about 100° F for a day or two. That is all there is to it!
Sincerely,
Donald Clark, CSM IMG
Editor’s note: You could also try this vacuum method for re-oiling emeralds.
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