Ultrasonic cleaners are great for cleaning jewelry. Caution should be taken to insure that the jewelry being cleaned will not be harmed by the extreme vibrations produced by the ultrasonic action. Hard stones such as diamonds, sapphires and rubies are safe to clean in it unless there are cracks or inclusions. Soft stones should never be cleaned in an ultrasonic cleaner according to the International Colored Gemstone Association. The solution sold for use in these cleaners can get expensive. You can make your own homemade cleaner with a few simple ingredients that may already be around the house.
Measure 2 cups of water and place into the ultrasonic cleaner.
Add 1 teaspoon of ammonia to the water in the cleaner.
Pour 2 tablespoons of dish washing detergent into the mixture.
Turn the machine on and let it run for 10 minutes to mix the homemade ultrasonic cleaner solution and allow the ammonia smell to dissipate.