We all love clean and sparkly jewellery but sometimes it’s really hard to get rid of accumulated dirt particles with traditional cleaning methods. This is when you may need to consider an ultrasonic cleaner which uses ultrasound waves to break the dirt on your jewellery. However, it’s important to understand which gemstones you can clean with this device and which ones you may damage in it.
Diamonds and Ultrasonic Cleaners
Diamonds are very durable gemstones, but sometimes it may be very risky to clean them in an ultrasonic cleaner. This is especially true for the diamonds that have a significant amount of inclusions as ultrasound vibrations can affect the internal flaws and crack the stone. If this is the case, you’d better opt for professional cleaning.
The next risk-group is clarity-enhanced diamonds. Although these diamonds do not have visible internal flaws, they are prone to damage as well.
Clarity enhancement is made through laser drilling and fracture filling, meaning the crystal structure of a stone gets damaged during the enhancement process. This makes an enhanced diamond more likely to crack or even break when cleaned with an ultrasonic device. In such a case, it’s recommended to take the stone to a professional jeweller for cleaning.
And the last rick-group is colour-enhanced diamonds. If the diamond has been treated to enhance its colour, depending on the type of treatment, ultrasonic vibrations can undo this effect making the colour of the stone less vivid. That’s why, if you are purchasing a colour-enhanced diamond ask the jeweller if the colour effect will hold after cleaning.
Gemstones and Ultrasonic Cleaners
As a general rule, the less durable the gemstone, the more it is prone to damage in an ultrasonic cleaner.
The gemstones that have been filled or coated with oil, plastic or wax should not be cleaned in an ultrasonic device. Such treatments are used on emeralds, lapis lazuli, malachites and opals.
Another group is gems that have been treated by heat to enhance their colour, such as star ruby and star sapphire.
The gemstones that are susceptible to heat and high temperatures should not be cleaned by ultrasound as well. Some of these gems include tanzanite, topaz, moonstone, malachite, lapis lazuli, turquoise, zircon, synthetic gemstones and others.
As you can see most of the gemstones are not suitable for ultrasonic cleaning. Instead, you can use gentle cleaning solutions or just warm soapy water to make them clean again.

Organic Gems and Ultrasonic Cleaners
Organic gems such as pearls, coral, amber, ivory, jet and shell cameos are very soft and porous. They should never be put into an ultrasonic cleaner because they can easily get dissolved by the heat and vibrations.
The best way to clean them is to use warm soapy water.
What Can I Clean Using Ultrasonic Cleaners?
White, yellow, rose gold and platinum are safe to clean with ultrasonic devices. In general, you can clean most metals using ultrasonic, the exception is tungsten.
Hard natural gemstones such as untreated rubies can also be put in the device. Just make sure they don’t have many inclusions and any coating.
As a general rule, when purchasing any jewellery piece ask the jeweller if it can be cleaned with an ultrasonic cleaner. It’s better to make sure the jewellery doesn’t contain alloys or gems that may become vulnerable during the cleaning process.