What is soft and warm beneath your feet at the beach? It is sand, of course. Sand can be very different. Sand can be coarse. Sand can be fine. Sand is made up of tiny pieces of rocks and minerals. Many white sand beaches have sand that is made of quartz. Sand comes in many colors. Some sand is dazzling white like the sand dunes at White Sands National Monument in New Mexico. Those sand dunes are made of gypsum. Fine white sand is also found near coral reefs. It is often made of ground-up coral. .....