Great way to start a rock collection! Learn about the exciting hobby of rock tumbling with National Geographic. This set includes all the accessories you'll need to start polishing dazzling gems. Rock tumbling is tons of fun and a great way to start an extraordinary rock collection. Kids can use the included jewelry fastening to create beautiful homemade jewelry! This expansive set contains a heavy-duty tumbling machine and rubber tumbler barrel. A programmable timer ensures you get the perfect tumble time! You also get 1 pound of rough rocks to tumble, 5 jewelry settings, tumbling grit, and a detailed learning guide with instructions. Learn all about the fascinating way rocks are polished in nature, how gemstones are used in jewelry and much more in our full-color learning guide. 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 Rock 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. Expanded assortment available online. This item not carried in store.