Review on Explore Nature's Gems: NATIONAL GEOGRAPHIC Rock Tumbler Refill Kit with Mookaite, Kabamba, and More - Includes 8 Jasper Varieties, 4 Grit Grades, Jewelry Fastenings, and Learning Guide by Marcus Hardin

Great refill for the starter kit I bought from Nat Geo. The only downside, and why I gave it 4 stars, is that it doesn't really warn you about not putting them all on at once, or how to make sure it's a safe weight. I know some of that comes with knowing the process, but having a refill that's too heavy and breaking the glass isn't fun either. The tumblr was replaced for free, but it's still a bit of a hassle to have some rocks that wouldn't fall. It had some great parts and a few small ones that didn't need flipping, so I think that makes up for it, and of course my own ignorance played a part in that. A solid set as it comes with lots of decoration and reading material.