Ninety percent of Earth is made of minerals, natural materials that form the building blocks of the solid structures on our planet. In Minerals, students will examine the makeup of a mineral as they review such properties as hardness, luster, cleavage, streak, color and density. Learn where minerals can be found, and see the many different uses of these natural wonders, which include powder, tools, jewelry and medicine. A visit to an old silver mine shows how miners removed valuable silver ore over 100 years ago, while a fun, hands-on investigation demonstrates the crystalline structure of minerals. Part of the Earth Science in Action DVD Series. A Teacher's Guide is included and available online. 23 minutes. Grades 5 to 8.