The best insurance policy for your jewelry is to have it regularly cleaned and checked before you loose a precious diamond or gemstone.
For my entire career I have recommended people get their jewelry checked at least twice a year. It is easy to put a ring on, wearing it daily and forget that the prongs are vulnerable. Over time the metal your ring is made of wears away. This leaves your stone exposed and the next gentle blow could remove your stone before you realize it. People seem amazed when they lose a valuable gemstone. The prongs and tips that hold a gemstone in a ring are very durable, but in reality they are small piece of metal that can wear away or break off. A simple clean and check can detect these situations before you look down and see an empty ring.
Most often I equate the wear of a ring to the tires on your car. They may be guaranteed for 50,000 miles but before you know it you are driving on tires with 75,000 miles and due for a blow out. This same scenario happens with rings. Most prongs will last an average of 5 to 8 years. If you are wearing a ring for 20 years and have never had any work done to it, in all likelihood you may be close to a blow out.