National Geographic Rock Tumbler Starter KitRock tumbling is tons of fun for children (and adults!) of all ages and promotes an interest in geology and science as well as providing an excellent motivation to get out there and explore the natural world in pursuit of your own rocks to tumble and learn about. If that's not your thing, we've got you covered with our refill kits, with extra gemstones, grit and jewellery fastenings to keep you tumbling to your heart's content. It's never been easier