Emerald Fillers and Treatments
Emerald fillers can improve the beauty of these gems but also have some drawbacks. Learn how to choose the right filler treatment for a particular emerald.
6 Minute Read
Cleaning Emeralds
First, clean the emerald thoroughly. Warm conditions help the cleaning process. If you warm both the stone and the cleaning liquid or filler together, you’ll open the stone’s pores, which will allow deeper penetration.
Don’t boil the emerald or immerse it in hot liquid. You’ll crack or shatter the stone.
A simple overnight soak in a jar of the cleaning medium on a hot plate may be enough to clean the emerald. (Again, warm conditions, not hot).
Organic Solvents
First, try organic solvents. Organic solvents safe for use with emeralds include the following:
- Acetone
- Methyl alcohol
- Ethyl alcohol
- A methylene chloride solution for dissolving cured epoxy and polyester resins
These preparations can evaporate in air and leave a residue worse than the original problem. Therefore, use a covered container.
Acids
If the organic solvents don’t remove the contaminants, you can use acids. For an intense cleaning, try aqua regia, a mixture of one part nitric acid to three parts hydrochloric acid.
Please note: hydrochloric acid fumes are toxic. Just the slightest whiff will burn your nose.
If your emerald has orange or brown rust stains, you can remove them with a solution of oxalic acid.
Exercise …
Mark Liccini
The late Mark Liccini began his career as a stone carver in the 1970s and worked for many decades as a renowned lapidary. Mark mastered the art of gemology, gaining degrees from the Gemmological Association of Great Britain and the Columbia School of Gemology.
International Gem Society
Related Articles
Emerald Value, Price, and Jewelry Information
Seven Famous Emeralds and Their Stories
Emerald Origins: History and Identification
Emerald Transformation: Cleaning and Recutting a Natural Emerald
Latest Articles
Precision Faceting a Story Gemstone: Choosing Rough
32 Green Gemstones (How Many Do You Know?)
A Guide to Antique Georgian Jewelry
Hambergite Value, Price, and Jewelry Information
Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.
Get Gemology Insights
Get started with the International Gem Society’s free guide to gemstone identification. Join our weekly newsletter & get a free copy of the Gem ID Checklist!