Seashells have a simplistic beauty to them. The colors, shapes and delicacy of seashells make them a favorite with many people including myself. I love their fragile shapes and markings. Gorgeous.
Seashells are also very symbolic for protection and luck. They're linked to old superstitions. One superstition says if you wear a seashell on a necklace during Spring and Summer it will bring you good luck. (I wonder if having a seashell iPhone case during the warmer months could be the more modern version of this.)