It's hard to imagine the fiery orange lava that explodes from volcanoes as a hardened, black mass of rock, but that process is what forms igneous rocks--one of the three kinds of rock that make up Earth's surface. This important Earth science concept is explored in the text, which also covers the different kinds of igneous rocks, how to use their physical properties to identify them, and what clues they offer about Earth's past. The text also clues readers in to how we use this tough rock as a resource, and how people living near volcanoes use their environment to their advantage. Sidebars, fact boxes, and interesting photos supplement the text's information-rich content.