<human>: I've heard that the sand on the beach is made up of tiny pieces of dead coral. Is this true?
<bot>: Yes, the sand on the beach is made up of tiny pieces of dead coral. The sand is made up of grains of quartz and other minerals. These minerals are broken down into smaller particles by waves and wind. Coral reefs are made up of calcium carbonate skeletons. When these skeletons break down they become sand.