This heavy-duty Multi-Color rock tumbler from NSI does much more than ordinary rock polishers- it changes rough stones into beautiful high-luster semi-precious gemstones. The entire process takes approximately 14 to 17 days to achieve. If your child enjoys Nature and Geography this is the item for them. It will provide hours of Screen free entertainment. Develop Creativity and Imagination by making jewelry and key chains with the settings included in this set. Rough semi-precious stones including amethyst jasper agate and others and grit polish jewelry settings glue and instruction manual. The Contents are made from Child Friendly Material. This Heavy-Duty Rock Tumbler has everything needed to create beautiful Gems.