5Metamorphic rocks form deep below EarthХs surface. Over thousands of years, they make their way to the surface. Then they are collected for use as building materials, sharpened tools, and even fertilizer Interesting text and vivid photos engage readers in this fascinating book about metamorphic rocks. Additional special features, such as a rock profile, formation diagrams, and a rock cycle chart, will help underscore the key features of these useful rocks for confident students who are reading to learn.