I love collecting scallop shells from Sanibel. The colors are lovely, and even better, they come in many sizes. After they are removed from the water, the brilliant colors dim when dry. A way to restore the luster is to apply a light coat of mineral oil to the shells, let them sit for a few days to soak it in, and then, if they are still oily, wipe off the excess with a soft, lint-free cloth. The difference between the right and left sides is easily discerned in the photograph. The mineral oil I used came from Ace Hardware and is called Bayes, Wood and Bamboo Conditioner and Protectant. This product is a 100% food-grade mineral oil.