Because your diamond when worn naturally attracts grease or oil, they will need periodic cleaning.
Even when touching a diamond with your fingers natural oils from your skin will change the brilliance of your diamond, making your diamond lose its lustre or brilliance.
A simple way to keep your diamond jewellery looking beautiful is a weekly bath in a household cleaning solution. A simple window cleaner will work. But make sure you give it a thorough rinsing followed by a very light brushing using an old tooth brush to remove the oils and cleaning liquid.
Pay special attention to the underside of the ring and bottom of the stone, as this is where most of the oils or hand creams accumulate.
Make sure when using a brush not to apply to much pressure especially if the jewellery is old or fragile. This is a good time to check the diamonds are tightly set and none are missing.
Never use Chlorine, bleaches or abrasives when cleaning diamonds set in jewellery. This will remove the rhodium plating on white gold and could leave scratches which will attract even more dirt.
If the ring has fine claws or filigree work an ultrasonic cleaner is necessary to remove deep encrusted dirt behind the diamonds. High frequency sound waves and jewellery detergent fluid will remove hard to get to dirt and grime. Make sure this is done by a professional to avoid damage or loss of stones.