NSI Industries

NSI Rock Tumbler Refill Classic

The NSI Rock Tumbler Refill Classic kit includes 8 oz of precious stones. Kids can learn about minerals with this educational and fascinating product. Use this product along with your existing rock tumbler toy to watch these stones become shiny and beautiful. This product is useful for learning the principles of geology, gemology and more. It's a fun activity for days and nights indoors. Once they're polished, you can use the rocks to make jewelry or keychains, or jy for days and nights indoors. Once they're polished, you can use the rocks to make jewelry or keychains, or just enjoy their natural beauty. read more