Which cleaning solution should I use in an ultrasonic cleaner for silver jewelry?

ZKZ Editorial TeamMain answer · Product & gemmology desk

GIA recommends gentle solutions, or just warm soapy water, for delicate gems and for metals that are oxidised or antique, and warns that standard solutions can damage delicate materials and finishes. For plain sterling with hard, untreated stones, mild soap and warm water is the cautious choice.

What the source says

Fact GIA says ultrasonic machines generate high-frequency sound waves that travel through water or a cleaning solution, creating heat and pressure, and that they can dislodge dirt from behind gems.

Fact GIA says not to use an ultrasonic cleaner on fracture-filled diamonds or other gems with filled fractures, on organic materials such as pearls and coral, or on gems that have been coated or impregnated with oil, plastic or wax.

Fact GIA says to use gentle cleaning solutions formulated for delicate gems, or just warm soapy water, for delicate gems and for oxidised or antique metals, and that standard cleaning solutions can damage delicate gem materials and surface finishes.

Fact GIA says the vibration can sometimes shake gems loose or damage them if they are set with their girdles touching.

Our advice So check that stones are securely set before and after cleaning.

Our advice

Our advice Read your machine's manual, use only the solutions it allows, and keep sessions short.

Our advice Do not use an ultrasonic cleaner on plated, oxidised, coated or glued pieces.

It depends A report on a stone may tell you about detectable treatments, which affects whether an ultrasonic cleaner is safe.

A cautious process

Our advice If you decide to use a machine, keep the session short, remove the piece and look at it, and stop if anything looks different. Do not mix pieces in one bath, since hard stones can knock against soft metal. If you are unsure about a particular stone, ask the seller whether the stone was treated and whether the report mentions it.

Uncertain We did not verify a specific solution that is best for sterling silver, so we do not name one. We also did not find a verified time or temperature for silver.

Related reading: Is an ultrasonic cleaner safe for a silver diamond ring? · What Does 925 Mean on Silver Jewelry?

Sources

• GIA 4Cs, Can ultrasonic cleaners damage gems?

Fact = stated by the cited source. Our advice = editorial recommendation. Uncertain / it depends = limits of what can be said in general.