The amethyst has been a desirable gem for thousands of years. Today, the purple stones are mined all over the world and set into brilliant jewelry. Readers learn the geologic process that creates an amethyst as well as how the presence of iron or manganese may contribute to its color. Interesting fact boxes add even more detail to the main content, which covers topics supportive of the science and social studies curriculums. Full-color photographs bring readers close to this precious gem both polished and set and in its natural state inside a geode.