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Why Not Clean Emeralds Ultrasonically?

A close up look of zambian emerald cabochon

If you care about your jewelry, you'll want it to appear as good as it did when you first bought it. Your bejeweled treasures can be restored to their former glory using ultrasonic cleaners. However, there is one drawback: not all gems and jewelry can be safely cleaned with ultrasonic cleaners.


1. What is an Ultrasonic Cleaner?

Ultrasonic cleaning equipment creates heat and pressure by sending high‑frequency sound waves through water or a cleaning solution. Ultrasonic machines clean jewelry by dislodging dirt and debris from behind the jewels and other difficult‑to‑reach areas.

beautifully crafted zambian emerald in shield cut enhancing its beauty


2. Why Emeralds should not be cleaned ultrasonically?

Natural emeralds have natural inclusions and cracks. If you drop an emerald gemstone or jewel in an ultrasonic cleaner, the ultrasonic waves work their way into the cracks of the gemstone. This can cause the cracks to expand, and breakage of the stone is highly possible. When cleaning gemstones with surface‑reaching fractures, avoid using an ultrasonic cleaner. Many gems, whether treated or untreated, are sensitive to heat and temperature changes and should not be cleaned in an ultrasonic, regardless of whether they are treated or not.

A close up look of zambian emerald cabochon


3. Then how to clean and take care of your Emeralds?

Emerald is a gemstone with a Mohs scale hardness of 7.5 to 8, making it a gemstone that requires more care while wearing than other precious gemstones.

However, with proper care, they can last for generations.

1. Warm, soapy water coupled with gentle scrubbing is the safest way to clean emerald or emerald jewelry.

2. Emerald Jewelry should not be cleaned with steam or ultrasonically.

3. Emerald and emerald jewelry may need to be re‑oiled after several years, we advise only Johnson's baby oil which is generally recommended and accepted by the trade in order to maintain the natural essence of the emerald.

4. Soft micro-fiber cloth (selvet/polishing cloth/gem cloth) should be used to remove dirt or oil accumulated on emerald or emerald jewelry.

5. Emerald jewelry should be stored separately from other jewelry in order to avoid scratches on the stone.

zambian emerald and cushion cut kept with cloth and bowl


4. Which are other gemstones that should not be cleaned ultrasonically?

When cleaning organic gem materials, avoid using an ultrasonic. These porous materials should never be cleaned with an ultrasonic machine because the ultrasonic cleaner's heat and the chemicals in most cleaning solutions can damage them. Ultrasonic cleaners should not be used to clean pearls, coral, tortoise shells, ivory, shell cameos, jet, or amber. If the stones have been impregnated or coated with oil, plastic, or wax, don't use an ultrasonic machine. Gems like lapis lazuli, malachite, and opal are frequently subjected to these treatments. If the stone has been heat‑treated to increase color, stay away from ultrasonic cleaners. While transparent rubies and sapphires should be handled with care, star rubies and sapphires should never be cleaned with an ultrasonic machine. Many gems, whether treated or untreated, are heat and temperature-sensitive and should not be cleaned in an ultrasonic. Tanzanite, feldspar (sunstone and moonstone), fluorite, iolite, kunzite, lapis lazuli, malachite, opal, topaz, turquoise, zircon, and other stones are examples of these gems.

A close up look of zambian emerald sugarloaf



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