Traditional jewellery cleaning techniques

Ultrasonic Jewellery Cleaners

Ultrasonic cleaners work by using a high frequency (ultrasonic) pressure wave and passing it through a solution. The pressure wave causes the solution to form bubbles on the surfaces of the jewellery when placed in the solution through a process called cavitation. These bubbles scrub the surface clean removing grime, grease and dirt. The pressure waves penetrate into all the tiny gaps and recesses.


Ultrasonics are powerful, and it is extremely important to never use on delicate items. Even diamonds can have inclusions (small cracks and imperfections), the pressure waves will enter the inclusion and can cause the stone to fracture. Other more delicate gems such as emeralds will fracture very quickly and must never be put in an ultrasonic. It is also risky to clean items with pave settings – the stones often fall out…


Although ultrasonic cleaners are extremely effective for removing dirt, grime, grease and particles, but they will not remove tarnish. Unfortunately tarnishing tends to be the biggest issue when cleaning jewellery.


The reason that an ultrasonic cleaner will not remove tarnish is that tarnish is a chemical compound. It therefore requires energy to remove. The energy to remove tarnish can be mechanical – re-polishing, or a reactive chemical – such as a silver dip cleaner, or electrical – ionic cleaning such as our JCR system.


Not all ultrasonics are created equally. A quality commercial grade ultrasonic tends to have multiple transducers, and the pressure waves are constantly monitored and adjusted, and the frequency tuned to suit the items they are cleaning. At the other extreme, very cheap ultrasonics are often just “sonic” cleaners. They use a much lower frequency, and simply vibrate the solution – and are only marginally better than using a cleaning brush with detergent.


Ultrasonics are fantastic for removing dirt, grease and grime, but must be used with extreme caution. They are a crucial tool for manufacturing jewellers. An ultrasonic will not remove tarnish, and if used incorrectly can be extremely destructive to delicate items.


Silver dip chemical cleaner

Chemical dip cleaning solution will normally remove tarnish very effectively from silver. It performs tarnish removal  by using a reactive chemical.


Chemical dip cleaners are normally acidic, and will damage natural stones, and gradually erode the polished surfaces of delicate jewellery. It is important not to allow it to come into contact with delicate stones – so it must be very carefully applied with a brush.


Dip cleaners also tend to be dirty, smelly and unless cleaned will leave a toxic residue on the surface of the jewellery. If the jewellery is placed in an ultrasonic to remove the residue, the chemical can form an aerosol and be breathed in.


Many silver dip cleaners use “natural chemicals”, be aware that natural does not necessarily mean safe or non-toxic!

Jewellery polishing cloth

A jewellery polishing cloth is simply a cloth containing a fine abrasive compound.


They remove tarnish by removing a small amount of precious metal along with the tarnish each time they are used. They will gradually round off details and sharp edges, and will spoil patinated surfaces.


Polishing cloths are a very cheap and effective way brightening dull jewellery – but this is at the cost of gradual loss of metal.  They are also good for removing fine surface scratches.


The irony is that the precious metal is actually already polished underneath the tarnish – and why re-polish an item that is already polished?

Steam Cleaner

A steam cleaner is a machine normally only used by jewellers. It heats  water up into high pressure steam. This is released as a steam jet directly onto jewellery. As it passes over the jewellery, and through chains it blasts off accumulated grease and dirt.


A steam cleaner brightens jewellery by removing the oil, skin flakes and grease from handling. It will not remove tarnish.


In use, most steam cleaners tend to smudge the grease and oil to the back of the item being cleaned without actually removing it…


Steam cleaners tend to be very large, noisy, potentially dangerous, and can crack delicate gems through thermal shock.

Jewellery Tumblers

A tumbler is a motor driven rotating barrel. The barrel contains lots of little ceramic or stainless steel shot. The shot can come in various sizes and shapes. A small amount of liquid polish is mixed in with the shot.


Items of jewellery are placed inside the rotating barrel, and the mechanical action gradually polishes the jewellery.


These certainly do work well, but extreme caution must exercised – the mechanical action will damage the surface of delicate gem stones. Also as with all polishing techniques, small amounts of precious metal is removed along with the tarnish.

Jewellery Cleaning: Abrasive Cleaning & Polishing Techniques

Our in-house 2 part jewellery cleaning documentary


Part 1: Outlines traditional jewellery cleaning techniques. Covers abrasive cleaning techniques, chemical dips, polishing cloths, and ultrasonic cleaning. Also describes how to prevent damage to jewellery set with delicate stones.

Jewellery Cleaning: Ionic Silver Tarnish Removal

Our in-house 2 part jewellery cleaning documentary


Part 2: Focuses on non-destructive cleaning methods; uncontrolled electrolysis and controlled electrolysis – introducing and demonstrating the JCR Ion-stream commercial Jewellery Cleaner.