Rocks and minerals are important for many reasons. Natural processes break down rocks into soil that is used to grow food for people and animals. Minerals from rocks are also used for fuel, tools, jewelry and building materials. Minerals are necessary for proper cellular function and all bodily processes, more so than vitamins, as vitamins cannot function without minerals present. Minerals are also needed for tissue rebuilding and healing in the body, as they are the basic building blocks of muscles, tissues and bones.