Turn rough rocks into beautiful, polished stones that you can use to make charms, bracelets, keychains, and more. Begin by tumbling the included rocks in a barrel with water and grit, then repeat this cycle using progressively finer grits. In just weeks, the Smithsonian Rock Tumbler mimics the process that takes oceans thousands of years! • Turn rough rocks into beautiful, polished stones! • Includes accessories to make charms, bracelets, and keychains. • Mimics the same process as the ocean. • STEM content teaches about different types of rocks and how they form. • Ages 10+