What Not to Put in an Ultrasonic Cleaner: Jewellery and Glasses Safety Guide

Ultrasonic cleaners can make routine care easier, but not every object that fits in the tank belongs there. The safe answer depends on the material, construction, condition and care instructions for the individual item.

Before using any cleaner, check the instructions supplied with both the item and the machine. If you cannot confirm compatibility, use a gentler manual method or ask the item’s manufacturer, a jeweller, an optician or another relevant professional.

Why compatibility matters

Cleaning equipment moves liquid into narrow gaps that can be difficult to reach with a cloth. That same action can reveal existing weaknesses. A loose stone may become more noticeable, a glued component may separate, or moisture may reach a part that was never designed to be immersed.

Do not treat “waterproof,” “water-resistant” and “safe for ultrasonic cleaning” as interchangeable terms.

Jewellery that needs special care

Porous or fragile gemstones

Pearls, opals, emeralds, turquoise and other porous, treated or fracture-filled stones often need specialist care. Do not place them in an ultrasonic cleaner unless the maker or a qualified jeweller confirms that the exact piece is suitable.

Loose, glued or damaged settings

Avoid pieces with loose stones, cracked settings, visible damage or glued decorative elements. Cleaning cannot repair structural damage and may worsen an existing weakness.

Antique and intentionally oxidised jewellery

Antique finishes, enamel, patina and intentional oxidation can be part of the design. Ask a jeweller before using a mechanical cleaning process that might alter the finish.

Glasses and coated lenses

Frames, hinges and nose pads collect oil and residue, but modern lenses can include anti-reflective, tint, mirror or other coatings. Do not assume every coating tolerates immersion or vibration. Check with your optician or eyewear manufacturer, especially if the coating is scratched, peeling or already damaged.

Read our detailed guide: Can you clean glasses in an ultrasonic cleaner?

Watches and electronic items

Do not immerse a watch movement, smartwatch, earbud, hearing device or other electronic product merely because part of it is described as water-resistant. A removable metal band may be suitable when its manufacturer permits it, but it should be separated from the watch body first.

See our watch-band and small metal accessory guide.

Dental appliances and personal-care items

Follow your dentist or appliance manufacturer’s instructions for retainers, dentures and removable dental appliances. Avoid treating a household cleaner as a steriliser or medical device. Washable beauty tools also need material-specific care; never immerse tools containing electronics, batteries or absorbent components.

Compatibility checklist before cleaning

• Identify the material, coating, stones and adhesives.
• Look for loose parts, cracks, peeling coatings or previous repairs.
• Confirm that the item may be immersed in water.
• Check whether the manufacturer permits ultrasonic or vibration cleaning.
• Start with clean water unless an approved solution is required.
• Stop if the item changes appearance or a component becomes loose.

Choose the cautious option

If compatibility is confirmed, the NudgePickr ultrasonic jewellery cleaner offers a compact, water-first method for compatible jewellery, glasses, removable watch bands and small essentials. For broader care options, read how to clean jewellery safely at home.