Diamonds are hard and durable; however, these beautiful stones are not immune to damage. They are susceptible to chipping, cracking and scratching if struck on a hard surface just the right way. If your cherished piece of diamond jewelry ever falls prey to imperfections, such as a scratch, there are a few at-home methods to try to help return its luster and newness.
Spread white toothpaste onto the scratch, rubbing it in with your finger.
Allow the paste to dry on the diamond before polishing it with a soft cloth. This should help make the scratch less noticeable.
Take the damaged diamond to a jeweler if the scratch remains. Depending on how deep the scratch is, the diamond may need to be reset, professionally repolished or recut.