Medallions occasionally make appearances in various types of Nancy Drew mysteries, as well as in the books. They are highly valued pieces of ornately decorated stones or jewelry that are a treasure to its owner.
Three medallions were the center piece of the story in Treasure in the Royal Tower, where Nancy had to locate all three medallions that had belonged to Marie Antoinette, and I personally think are most beautiful. Not only are they pretty, but they served several more purposes in the game. I won't spoil it for you in case you haven't played it yet.
In a more recent game, The Captive Curse, there is a medallion fastened as a necklace. The original medallion necklace was worn by girls who were reportedly attacked by the monster. Because of this story, there are replicas in the Castle souvenir shop. So if you wanted to lure a creepy monster to yourself, just wear a necklace!
Our next Nancy Drew game, The Shattered Medallion, has the medallion right in the title. This is another very important medallion, as you will soon learn. Obviously it is broken into five parts and has a beautiful carving on its face. What do you suppose this medallion's story is? Will it serve a purpose? Will it lure you to your death? Is it symbolic of something?