All jewellery eventually needs to be cleaned, due to body oils, air pollution, or even food. Ultrasonic jewellery cleaners, once only available for use at jeweller's shops, are now manufactured for home use. There are special cleaners sold to go in the ultrasonic cleaners, but you can also make your own.
How ultrasonic jewellery cleaners work
Unlike passive cleaning methods, like soaking jewellery in a tray with solution in it, ultrasonic jewellery cleaners use ultrasonic waves and sometimes heat to knock grime off jewellery. This sparkles and shines the jewellery. After the cleaner has done its job, you'll need to remove the jewellery and give it another gentle scrub with a soft brush to remove any leftover residue, then rub it with a soft cloth to shine it up.
Making your own ultrasonic cleaner
You can buy an ultrasonic jewellery cleanser, but it's also quick and cheap to make your own with a few household ingredients found in any chemist's shop or supermarket. These are the same ingredients used in commercial solutions. You'll need 474 ml (2 cups) of water, a teaspoon of plain household ammonia, and two tablespoons of a mild detergent, such as washing up liquid. Make sure that the detergent does not contain sodium lauryl sulphate, which will make the mix sudsy. Mix the solution in a bowl with a plastic or wooden spoon, a metal spoon will react to the ammonia, being careful not to churn up the soap, and then pour it into the ultrasonic cleaner. Or pour all the ingredients into the ultrasonic cleaner, then turn it on for a few minutes to mix the ingredients.
Hard gemstones, such as diamonds, sapphires, and rubies, do fine in an ultrasonic cleaner with an ammonia solution. Platinum, gold, and silver do as well. Always inspect your stones to make sure they're not loose in their settings; an ultrasonic cleaner will loosen them even more. Also, if the stones have any small imperfections, also called inclusions, the ultrasonic cleaner could cause those to become larger. You should never put soft stones, like opals, pearls, amber, marcasite, and the like in an ultrasonic cleaner, nor should you use any ammonia-based solution with these soft stones, as they will lose their lustre and become damaged.