No. An ultrasonic cleaner can remove stubborn dirt, but the wrong piece can come out damaged or missing a stone. Before switching one on, you need to know the gem, any treatments it has received and whether the setting is sound.
GIA explains that ultrasonic machines use high-frequency sound waves through liquid to loosen dirt in hard-to-reach places. That cleaning action also creates a reason for caution: vibration can loosen stones or damage gems whose edges touch.
Which jewelry should stay out?
GIA's jewelry-care guidance warns against ultrasonic cleaning for organic gems such as pearls, coral and amber, as well as gems with certain fillings or coatings. Emeralds commonly receive clarity-enhancing treatments that can be affected by cleaning. Opal, turquoise and tanzanite are among the other materials that need particular care.
A stone's name alone is not enough to choose the method. Treatments and the condition of the entire piece matter. If you do not know what you have, put the machine aside and have a knowledgeable jeweler examine it.
What about diamond jewelry?
Diamond's resistance to scratching does not make its setting immune to vibration. GIA's Diamond Care and Cleaning Guide advises against harsher methods, including ultrasonic and steam cleaners, for home use. Professionals inspect the jewelry for loose stones before using them.
GIA's diamond-cleaning advice also calls for caution with included diamonds and says to avoid ultrasonic cleaning for fracture-filled diamonds. The risk can involve the filling, the stone or the mounting.
What can you do at home?
For diamond jewelry suitable for gentle washing, GIA recommends water with a few drops of mild dish soap and a soft, clean toothbrush reserved for jewelry. Be gentle around fragile settings, rinse carefully and dry with a lint-free cloth. Close the drain if you work over a sink.
Do not use toothpaste or chlorine bleach on diamond jewelry. Do not transfer this routine to every gem in your jewelry box: pearls, treated gems and delicate or antique pieces need care matched to their materials.
The useful question for your jeweler is specific: “Is this exact piece safe for an ultrasonic cleaner?” A yes for one ring does not cover the next.
About the author
Erica Diggs is a GIA Graduate Gemologist and the founder and editor of Drip With Diggs.
