Tidepool Tim says, "It's important to recognize the difference between a dead sand dollar and a live one! You may have seen bright white sand dollars for sale in gift shops, these are definitely bleached, and definitely dead. Dead dollars on the beach will usually be a much lighter color than live ones, probably a tan or light grey color. These have smooth bottoms. In contrast, live dollars have 'fuzzy' bottoms, which are their tube feet."