Let's rock and roll! Amp up your rock collection and explore the secrets of geology with the Thames & Kosmos Rock Tumbler! This custom-designed, user-friendly machine allows budding geologists and gem collectors to transform rough stones into beautiful polished rocks while exploring topics like erosion, weathering, and the geological rock cycle. The kit comes with an assortment of authentic rock samples to get you started — including amethyst, aventurine, rose quartz, and more — as well as four polishing grits. Use the included jewelry settings to create accessories from your specimens. The powerful, long-lasting motor is built with durability in mind: once you've polished the included rocks, you can continue your experiments by tumbling rocks, glass, wood, and other materials you collect on your own. The leak-proof, noise-reducing barrel and built-in timer also aid in ease of use. The included manual and poster guide children on their rock-polishing adventures, providing usage instructions as well as a wealth of scientific information about different types of rocks, how they are formed, and more.