Learn about the exciting hobby of rock tumbling with National Geographic!Rock tumbling is tons of fun and a great way to start a beautiful rock collection.This set includes all the accessories you?ll need to start polishing dazzling gems.Kids can use the included jewelry fastening to create beautiful homemade jewelry!Contents and Features:? High-quality tumbling machine with powerful motor that will last for years? Automatic shutoff timer so you can set it and forget it? Noise reducing leak-proof barrel with stainless steel lid? Half pound of gemstones from around the world (9 types) and four grades of grit? Jewelry fastenings so you can create your own unique jewelry? Full-color information guide with cool facts about each of the gemstones included? Easy-to-follow rock tumbling instructions? 2-year manufacturer warrantyRock tumbling is a fun activity for children of all ages and promotes an interest in geology and science.Introduce your kid to science the fun way! Join National Geographic as we inspire future generations by showing them the wonders of the natural world.National Geographic Toys is proud to provide a100% satisfaction guarantee with all our products so that you can buy with confidence.About the National Geographic Society: With a mission to inspire people to care about the planet, the 126-year-old National Geographic Society is one of the world?s largest nonprofit scientific and educational organizations.National Geographic?s net proceeds support vital exploration, conservation, research, and education programs.