








🪨✨ Turn Rough Rocks into Polished Gems — Your Next Creative Obsession Awaits!
The National Geographic Hobby Rock Tumbler Kit is a durable, leak-proof rock polisher featuring a 7-day timer and speed control. This all-in-one STEM kit includes 1/2 pound of rough stones with nine gemstone types, tumbler grit, innovative GemFoam polish, and jewelry fastenings. Designed for ages 8+, it combines educational value with creative fun, supported by award-winning Blue Marble customer service.






































| ASIN | B086Z6ZB7R |
| Age Range Description | 8 years and up |
| Best Sellers Rank | #2,129 in Toys & Games ( See Top 100 in Toys & Games ) #406 in Educational Science Kits |
| Brand Name | Blue Marble |
| Customer Reviews | 4.4 4.4 out of 5 stars (3,671) |
| Educational Objective | STEM |
| Included Components | Complete Rock Tumbling Kit |
| Is Assembly Required | No |
| Item Dimensions | 13.11 x 5 x 8.15 inches |
| Item Type Name | Hobby Rock Tumbler Kit |
| Item Weight | 1.9 Kilograms |
| Language | English |
| Manufacturer | JMW Sales, Inc. |
| Manufacturer Maximum Age (MONTHS) | 1188.0 |
| Manufacturer Minimum Age (MONTHS) | 96 |
| Manufacturer Part Number | NGHOBBYTUMBLER2 |
| Material Type | Plastic |
| Model Number | NGHOBBYTUMBLER2 |
| Set Name | Rock Tumbler Kit |
| Size | One Size |
| Sub Brand | National Geographic |
| Theme | Geology |
| UPC | 816448028830 |
| Unit Count | 1.0 Count |
J**.
Fun product and fantastic customer service! 👏
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!
S**S
bad tumbler.. UPDATE
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.
M**A
Started using it as soon as I got ando love it
-Polly plastics grit and polish are better than the grit provided and gives you a larger amount of grit - the tumbler has been running for about 2 weeks and is still working amazingly -the grit that is provided by National Geographic works fine but I prefer the Polly plastic one -Ceramic media really helps and the tumbler does not Provide any -It is extremely easy to clean I just rinse the tumbler in my sink for about 30secs. Then dry it off with a paper towels and it’s ready to go -it comes with a detailed instruction Manuel that explains how to use the tumbler and how to get the best results -national geographic will replace most items in case of damage if you email them -it is very loud I put mine in my basement and I can hear it upstairs -the speed is great but it still takes about 3-4 weeks to fully complete the tumbling process including grit and polishing - there are 2 caps on the tumbler to prevent leaking - the setting go to 7 days straight for tumbler to You can easily set how long you want the rocks to tumble for. Over all very beginner friendly and great quality never had a problem with leakage or any sort of damage and I’m thinking about getting one for my sibling the only main downside is how loud it is
G**A
Fun project
Daughter got this from santa this year. It taked a month or so to run a full cycle through all the grits. The unit runs well but is a little loud. We are on the 3rd grit out of 4 and the rocks are looking really good. You start with some rough dusty rocks that you can almost not tell what they are but quickly they polish and start looking nice.
P**.
Quality product
Bought for a gift the 40 year old man loved it
T**A
Fun and Educational — Great for All Ages!
The National Geographic Hobby Rock Tumbler Kit is fantastic! It’s sturdy, durable, and completely leak-proof, which makes it easy to use without any mess. The 7-day tumbling process is engaging and gives you a real sense of progress as the rocks slowly polish to a shiny finish. The kit comes with everything you need, and it’s both fun and educational — perfect for kids or anyone interested in geology. Overall, a high-quality, enjoyable kit that’s definitely worth the purchase!
L**M
Happy then sad then happy again
Was so very happy with this unit for several months. Received and started using by Aug 15th and the motor died Nov 10th. I have a cheap one from H.F. noisy as hell but just won't die. Loved how quiet this one was, the drum is fantastic, rocks and info great for first-timers. UPDATE!!! the company reached out and offered a refund, I asked for a replacement instead, and they agreed and shipped one out. great customer service.
C**S
Very loud
Very loud and takes forever to tumble rocks I mean forever I’ve been trying to tumble rocks for over a month now my neighbors can hear the noise in the apartment downstairs
C**L
cadeau de noel pour mes parents qui aime faire des bijoux fantaisies. il me dise que le procédé est long mais que le résultat est bon. les pierres qu'ils ont ramassé eux même on perdu 50% de leur taille.
M**N
It is incredibly loud. There is no place in my house that I can run this overnight. I live in Canada, cannot leave water in unheated shed. There is enough abrasive material for one tumbling cycle. The cycles take 3 - 6 days each. Many of the included rocks are so small, they are unusable after the 2nd or 3rd cycle. This product could be better. It does exactly as intended. My son is more knowledgable since we purchased this product.
G**H
This is a great introductory rock polisher and does an excellent job. The manual could include more tips on practical rock polishing. The supplied rock mix contains various types of rocks that in some cases should not be polished together as the softer rocks are destroyed by the harder rocks. That being said it is part of the learning experience. Please note the machine is noisy and may need a sound proof box unless you have a shed some distance from your home.
R**E
Tolles Produkt
R**N
Mi hija se li ha pasado genial puliendo piedras
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