As a store that does a lot with repairs we often have customers that come in to get a diamond replaced. There hasn’t been one person that hasn’t asked “Why did a diamond fall out?” Unfortunately there is no straightforward answer; there are a number of factors that can cause a diamond to fall out of a ring.
Normal Wear and Tear
Diamonds are the hardest naturally occurring substance on Earth, unfortunately a typical ring isn’t made entirely of diamond (yes it does exist), so the metal holding the diamonds are going to be more susceptible to everyday wear.
Each time you wear your ring the prongs wear down fractionally, just as the tires of a car do. Just like a car’s tires, prongs require maintenance over time and if that maintenance is not performed there’s more risk of a diamond falling out.
Often damage to prongs goes unnoticed. This could be from wearing your ring during heavy activity, frequent chemical exposure (such as swimming) or frequently snagging your ring on clothes or hair. To prevent this type of damage remove your rings before any heavy activity or exposure to chemicals. If you notice frequent snagging bring your ring right into your jeweler who will assess if the prongs need to be worked on.
Get your rings checked by a jeweler about every 4-6 months. It may be hassle to put that on your calendar, but it’s a lot less expensive to re-tip prongs than to replace missing diamonds.