Standard insurance policies let you insure jewelry worth up to $1000. However, chances are the beautiful diamond ring you pick out for your fiancée is worth more than that. Moreover, this only covers the items partially – if they are lost, damaged, or stolen, you only get a small percentage of their worth after making a claim. Another problem with insurance is that it cannot bring you back a lost or damaged piece that held sentimental value. Stuff like that stays gone for good.
Insurance coverage can be increased by buying an endorsement for an existing policy. For instance, you can get your homeowners’ policy upgraded for about $5000, and start getting insurance protection for the ring as well. The specifics of this would need to be checked of course.