National Geographic Rock Tumbler Kit – Hobby Edition Includes Rough Gemstones, and 4 Polishing Grits, Great STEM Science Kit for Geology Enthusiasts, Rock Polisher for Kids and Adults

Are you wondering if it works well? It does! Any problems? None! Results? Incredible, I was truly shocked! Pros: Almost no assembly, at all. Extremely easy to understand the directions (Tumbling time will vary depending on the rocks. Don't let it scare you away when it says one phase should tumble for 6-8 days (I haven't had to tumble any that long! The longest has been 3 days). That being said, an extremely hard rock that's very jagged may need more time. Using the rocks they include, or your own collection of crystals/gemstones is a great route. A plain piece of gravel or a rock of that type is very hard and dense and may take more time (who wants polished gravel anyway though?) Extended project to do with children, lots of engagement. Because their are 4 different grit types with different purposes, the children get to return to their project, dump the rocks and check on the progress and start a new phase. It's a great opportunity to teach to teach about erosion, and show / explain what a rock looks like through millions of years of erosion and then further explain how incredible it is that we are doing this project together that mimics what nature does, we are polishing these rocks in a few weeks that takes millions of years to do in nature! It's a wonderful learning opportunity for children, as well as an extremely engaging project that although it may take quite some time for it to finish, the ongoing project itself is what makes it fun. Returning to the rocks and seeing the progress, (we actually started taking pictures each time we open it so then we can look back on the pictures and see how the rocks have changed!). I cannot say enough how great of a project this is for children to get them excited about science! Personally, I find this to be very satisfying regardless of children. This would be an extremely fun hobby for an adult as well, the above is not to say that this is a children only experience. Use or find or buy your own natural gemstones or softer rocks (look in River beds if you can!). Tumble them, polish them, and then make your jewelry or just save them to display. It's quite a satisfying feeling to see the project from beginning to end, and to know that the beautiful smooth shiny rocks were not store-bought, but that you did this with that with this machine! Cons: I've been through the tumbling process in full, twice now. I honestly cannot think of any cons at this point. It's not to say that no one has had issues, but the machine I received functions perfectly and I have had no issues with leaks or ill-fitting pieces, tearing of the belt or anything of this nature. I did take a very small amount of oil on my fingertip and lightly rub it on the belt to keep it lubricated, with the constant friction I could see how the belt can eventually wear down just like any other belt of this nature whether it's in a car or in a fan. So, keeping it very slightly lubricated will help with the health of the band. Should it break, the kid includes an extra belt and it is incredibly easy to repair, the belt is divisible and an outside piece of the equipment you simply take one off and put the other on there is no sophisticated way of connecting the belt, it is truly something my six-year-old could do with almost no instruction, so an adult will have zero issues with that! If you are interested in rock tumbling, or you just want a very fun project for your children to stimulate their interest in science or to just keep them busy using their imaginations (regarding the possibilities of what to do with the rocks, and imagining whether it will look like and the brilliant colors!) - then this is absolutely a perfect kit to start with. DO: Make sure to not put too many rocks. I've never filled mine more than one third of the way, and I wouldn't recommend doing more than that. The amount of rocks you can tumble at a time will vary depending on the size, but I also recommend not doing anything smaller than a dime because during the tumbling process it could crack and chip. I would also recommend not doing anything larger than a half dollar as well (height and width, and that'd be on the largest size). Remember, this is just the hobby edition. I do have to say though, the results are quite sophisticated for just a hobby edition! All in all, it's an excellent piece of equipment to buy if you're interested in rock tumbling but are unsure if you would stick to it or are not ready to spend a few hundred dollars on a professional Tumbler. ** I did read a few comments about the machine leaking, I have not had this problem at any point. Make sure you are putting on the inner lid correctly, as well as the top lid, then turning the black lid securing piece as tightly as possible. If you do end up having problems, I highly recommend exchanging instead of giving up, because I really have seen that it works and I just want everyone who wants to try this to have the experience I've had! It's been great fun. Wonderful purchase, no regrets!

Love it, very nice quality but for those interested in this for children, it is kinda loud so make sure you have somewhere you can put it so it won’t annoy people like a garage or basement , overall though it works very nice!

This was very easy to use. As a first-time hobbyist, I've always wanted a rock tumbler, and the instructions and suggestions were very clear and easy to follow. I started making tumbled stone jewelry as gifts for friends, family, and the steady stream of caregivers and medical professionals my husband and I see on a daily basis. We are both disabled and I (despite my own issues) am my husband's main caregiver. Rock tumbling and making jewelry have become my escape from the daily chaos of our lives, my relaxation from my anxiety and chronic pain disorders, and something I can share that is uniquely mine. I've had this tumbler for a year now, and have enjoyed it immensely. Recently, however, the belt broke. Not a big deal but, since replacing the the broken belt with the included replacement belt, the unit was fine for a couple of weeks before it suddenly stopped one night in the middle of a 7-day tumble. I tried re-seating the canister and started it again, only for it to stop again (with all of the lights flashing) 30 seconds later. I looked online for any suggestions dealing with the issue, and came up with several possible things that could be causing the problem. I removed the belt and carefully cleaned the rotating pins. I cleaned between the base rollers and the buffer pads, and made sure no pet hair or dirt was built up anywhere that could be causing the stoppage. I removed the canister and removed half of the stones in case the weight was the issue. Despite all of this, the unit would not keep spinning, and kept "freezing " within minutes of restarting. Today is Monday 1/12/26. My husband is in the hospital due to an infection, and I am trying to catch up on some things I've been putting off due to time constraints. So, I called the customer service number listed on the box. Since the product was purchased from Amazon, I was able to supply the NatGeo/BlueMarble help desk associate with the date and order number of the unit. I was also able to give them the SEC/lot number information since I still have the box. I then found out that I was 13 days past the warranty/exchange period. Some companies would simply refuse any liability because it was past the warranty date, but not this one. After hearing my issue, what I had done to address the problem, and getting the pertinent information about my purchase of the item and the unit itself, they generously offered to replace the entire kit. I was definitely not expecting that, but it was a great surprise and absolutely made my day. In conclusion, the tumbler is great for a first-time or young user. The directions are easy to follow. The stones are beautiful, if a bit small, but perfect for jewelry or other things. There is an included booklet with sample pictures to help you identify your stones, which I found very helpful. Above all, NatGeo and Blue Marble are VERY responsive to any issues and actually stand behind their product, a rare find in today's marketplace. I highly recommend this product for young or beginner tumblers. It took me until my 57th birthday to get one, and I've been having a blast!

Update. Quit working just flashes lights. Good for small kids. Not good for someone wanting to tumble a large amount of stone. Comes with one small grit pack for stones it comes with and one in each pound of rocks. The rocks are crap. U get very little agate I got no amethyst, some pale amazonite, and the rest is various jasper. Oh did get a large chunk of sodalite that wont fit in tumbler. Tum let is NOISY!!! And it does take about 2 weeks to tumble stones so I advise u put it in the garage. Unless your in a cold climate because u must use water and grit to tumble stone. Also the jewelry it comes with, well all I can use are the cord for necklace.. u get 3 jewelry" kits" in this package. I can use the stone cages from the necklace and key chain, the earrings are clip ons that require an epoxy glue and same with the tiny adjustable ring. Honestly would have saved money buying a tumbler and bulk grit separate. All of this can also be found on wish. Just because it's a nat geo product doesn't make it better. The drum is all rubber with a stainless cap, and u get the base, plug, and an extra "belt" that's hidden under the cap. There are rocks in a bag inside the tumbler when u get it. None of jewelery quality. Lot of nice tigers eye chunks but u can buy that cheaper here or wish. If I wasnt a prime member and had to pay shipping.. this is 7+ pounds.. I would have not gotten it. It will work for now because ups was 3 days late from a snow storm. I'm starting Into lapidary and jewelry making so I'm sure I will get a lapidary wheel and bench as I improve. All jewelry findings can be found on amazon.

I originally purchased this in March 2024. I used it pretty regularly for 9 months and it worked wonderfully and I loved the results I got with my rocks. I paused using it for a few months and when I tried to start tumbling some rocks again, the tumbler would barely start moving and then would stop all together. Opening it up and cleaning it up seemed to help for a few minutes but then it would stop again. I opened it again and the connections all seemed fine but I wondered if the motor was just worn out. I contacted the manufacturer Think Blue Marble and they immediately replied to my email saying that it sounded like it was a weight sensor issue. They offered to send me a one time replacement free of charge! I provided my address and within 72 hours of my initial email I had received a brand new natgeo tubmler set in the mail! 100 stars for amazing customer service and standing behind their product! I'm just about to finish up the first stage in this new tumbler. Thank you Think Blue Marble!!

We used this to tumble half the rocks that came with this tumbler, then tried to do some more of the other rock that came with it and it started messing up, and now it runs for about 3 mins and turns off. I have been trying to tumble rocks on the first stage for three days now. This machine is to expense to only tumble half of the rocks they send. Won't buy again and will not recommend . UPDATE.. We had an issue with the first one we recieved, I contacted them and they replaced it right away. Thank you very much for your great customer service.

**updated review below--- we got shiny rocks!** We bought this for our son as a 7th birthday gift. It's the perfect mid-range rock tumbler! It's sturdy and doesn't seem like it will break. It's been running now for over 2 weeks. It's definitely not silent, but with its rubber barrel, I suspect it's tougher and quieter than one with a plastic barrel. We keep it in the basement, but can see it'd be annoying if it was somewhere in the house. It has a handy feature where you can set it for up to 7 days and it'll tell you how many days are left- great for a kid! It includes a nice little instruction manual with information about the history of rock tumbling and description of the rocks included. It's a nice, reasonably-priced kit that includes everything you need to start tumbling rocks right away! Update: now that we've completed a batch, I figured I'd add some info. We still think it's a nice kit! The little sieve that comes with the kit is very handy! Our final stones were smooth and lovely. However, they weren't really shiny. After some reading, we learned that there is a bit of an art to this and we need to be a little more meticulous in the cleaning of the tumbler between grits. Overall, though, our 7-year-old is quite pleased with the kit. We bought the jasper set and will try that next! Update #2-- SHINY ROCKS! We did a few batches and couldn't get shiny rocks and we lost interest. My kiddo is now almost 9 but just started becoming interested in geology a lot more. We decided to try again. After reading some about it, I decided to try a better brand of grit and IT WORKED! We bought Rock Tumbler Grit for 3 Pound Tumbler by Professional Grade Rock Polishing Grit And followed the instructions **carefully,** making sure to clean the tumbler tub very meticulously after each tumble. We also purchased tumbling pellets (Rock Tumbler "Sinking" Plastic Pellets / Beads Used For Final Polishing & Burnishing Stages) for the final two stages. The new grit had an additional stage which made all the difference. The jade set came out mostly lovely and shiny. They were not all consistently shiny, but I see promise! I added a picture using the flash to show off the polish. We're going to try the nee grit with a different set of stones now.

I bought this as something interesting to do, together with my Granddaughters, this past fall. I don't want criticize it too much. The tumbler itself functioned ok, instructions were clear and easy to follow. We used the premeasured 4 stages of grit and the stones provided (very small and not many of them), with the suggested time intervals. However, the end result, using the final polishing grit, was nowhere near the really highly polished shiny rocks one finds for sale in gift shop etc. After the fact, I found some really good Youtube videos on rock tumbling. I highly recommend that you check these videos out. One of the criticisms of the Nat Geo grits, is that they really aren't capable of a highly polished final finish. I believe that this product is a useful tool....still fun to try and could be a starting point, if you are willing to learn more about the tumbling process and you shop around for better quality grits (polishes) to use in the Nat Geo tumbler.