The Sand Dollar is a spiny, hard-skinned animal that is shaped like a coin. There are many different species of sand dollars. They live on the sandy sea floor, and most are found at depths of 30 to 40 feet (9-12 m). You can often find the dead "shell" of a sand dollar (called a "test") washed up on sandy beaches. If you break open a test, there are many hard, loose, white pieces; these were the teeth of the Sand Dollar. / kr NC