--- product_id: 48271698 title: "NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks" brand: "blue marble" price: "$155.83" currency: USD in_stock: true reviews_count: 13 category: "Blue Marble" url: https://www.desertcart.us/products/48271698-national-geographic-rock-tumbler-grit-1-49kg-polishing-grit-media store_origin: US region: United States of America --- # Polishes up to 9kg of rocks 1.49kg high-quality polishing grit 4-stage silicon carbide grit system NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks **Brand:** blue marble **Price:** $155.83 **Availability:** ✅ In Stock ## Summary > 💎 Transform Rough Rocks into Polished Masterpieces—Because Your Collection Deserves the Best! ## Quick Answers - **What is this?** NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks by blue marble - **How much does it cost?** $155.83 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/48271698-national-geographic-rock-tumbler-grit-1-49kg-polishing-grit-media) ## Best For - blue marble enthusiasts ## Why This Product - Trusted blue marble brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Easy Measure & Store:** Wide-mouth containers with screw-top lids and a 10mL scoop for flawless grit dosing. - • **Universal Compatibility:** Seamlessly works with all rock tumblers—maximize your gear’s potential. - • **Precision 4-Stage Polishing:** From rough shaping to mirror finish, every step engineered for perfection. - • **STEM-Approved Hands-On Science:** Elevate your geological knowledge with a premium educational tool trusted by pros. - • **Bulk Supply for Marathon Tumbling:** 1.49kg grit media powers your rock polishing projects for months without refill anxiety. ## Overview National Geographic’s 1.49kg Rock Tumbler Grit is a premium silicon carbide polishing media designed for all rock tumblers. Featuring a precise 4-stage grit system, it shapes, smooths, pre-polishes, and delivers a dazzling final polish to up to 9kg of rocks, gems, and glass. Packaged for easy measuring and storage, this refill kit is perfect for serious hobbyists and STEM enthusiasts aiming to elevate their rock tumbling experience. ## Description Product Description National Geographic Bulk Polishing Grit for Rock Tumblers aplus content video This rock polisher grit refill pack comes with enough high-quality silicon carbide grit to put a dazzling polish on up to 9 kg of rocks, gems, glass & more! The first stage provides initial shaping, the second smooths rock surfaces, the third pre-polishes rocks & fourth provides the final polish. Keep the fun rolling with National Geographic high-quality grit media! The National Geographic Rock Tumbling Grit Bulk Pack contains over 1.36 kg of rock polishing grit, compatible with any tumbler! This Kit Includes 4 Stages of Rock Polishing Grit 1 10 mL Grit Scoop Rock Tumbling Instructions This four-stage silicon carbide grit for rock tumbling systems is the ideal way to give rough rocks a smooth, polished look. The first rock polishing stage smooths rough edges and provides initial shaping. The second stage smooths the rock surfaces even more. The third stage provides a strong pre-polish, followed by the fourth stage which completes the grit polishing process. The 10 mL scoop in the grit refill kit ensures accurate grit measurements for every stage, allowing you maximize your grit usage for up to 9 kilograms of rocks! This rock tumbling grit refill pack is compatible with any tumbler on the market, but for best results, use with National Geographic tumblers and rock tumbling supplies, including ceramic media and GemFoam. We make the highest quality hands-on science toys, and all products are backed by exceptional service. With a mission to inspire people to care about the planet, the National Geographic Society is one of the world’s largest nonprofit scientific and educational organizations. Review: Perfect Refill Set - Perfect refill pack. More than enough quality materials to keep us tumbling rocks for many, many months. Great value and includes instructions, which was very handy as we misplaced the ones that came with the tumbler itself. Review: Perfect size for the rock tumbler! - Exactly what I needed, more grit for my tumbler! I recently got some of my own beach rocks; quartz and serpentine, possibly some granite, and I needed these to tumble away! Good size, easy to use, functions as it should, measuring spoon and instructions made it easy to use. Think this is probably fun for kids, but definitely is for adults! ## Features - HIGH QUALITY – This rock polisher grit refill pack comes with enough high-quality silicon carbide grit to put a dazzling polish on up to 9 kg of rocks, gems, glass, and more - EASY TO USE FOUR-STAGE ROCK GRIT - The first rock tumbling grit stage provides initial shaping, the second smooths rock surfaces, the third pre-polishes rocks, and the fourth provides the final polish - COMPATIBLE WITH ALL TUMBLERS - This complete 4-step tumbling grit refill kit works with all rock polishers. For best results, use with National Geographic tumblers and rock tumbling supplies - EASY TO MEASURE AND STORE - Each rock tumbling grit stage is packaged in a wide-mouth container with secure, screw-top closure - HIGH-QUALITY EDUCATIONAL TOYS - We're proud to make the highest quality hands-on science toys, and all our products are backed by exceptional service. If your experience is less than stellar, let us know and we'll make things right! ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B01MRKI4W0 | | Age Range Description | 8 years and up | | Best Sellers Rank | 49,079 in Toys & Games ( See Top 100 in Toys & Games ) 529 in Educational Science Kits | | Brand Name | Blue Marble | | Colour | Black | | Customer Reviews | 4.6 out of 5 stars 14,849 Reviews | | Educational Objective | Promote geological knowledge and provide practical learning experiences related to rocks and minerals | | Global Trade Identification Number | 00816448020636 | | Included Components | 10 mL Grit Scoop, 4 Stages of Rock Polishing Grit, Rock Tumbling Instructions | | Indoor Outdoor Usage | Indoor | | Is Assembly Required | No | | Item Dimensions | 14 x 14 x 10.8 centimetres | | Item Type Name | Rock Tumbler Grit - Rock Polishing Grit Media | | Item Weight | 1.78 Kilograms | | Manufacturer | National Geographic | | Manufacturer Part Number | NGBULKGRIT | | Manufacturer Warranty Description | We're proud to make the highest quality products which are backed by exceptional service. | | Material Type | Carbide of Silicon | | Maximum Age Recommendation | 1188.00 | | Minimum Age Recommendation | 96.00 | | Model Number | NGBULKGRIT | | Number of Players | 1 | | Operation Mode | Manual | | Set Name | Stone Bite Set | | Size | M | | Sub Brand | National Geographic | | Supported Battery Types | No batteries required | | Theme | Science | | UPC | 816448020636 | | Unit Count | 1.0 count | ## Images ![NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks - Image 1](https://m.media-amazon.com/images/I/81+X8uILF3L.jpg) ![NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks - Image 2](https://m.media-amazon.com/images/I/81UmLBS80lL.jpg) ![NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks - Image 3](https://m.media-amazon.com/images/I/81HKJsr8ghL.jpg) ![NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks - Image 4](https://m.media-amazon.com/images/I/81+kRL0M3qL.jpg) ![NATIONAL GEOGRAPHIC Rock Tumbler Grit - 1.49kg Polishing Grit Media for Any Rock Tumbler, Rock & Stone Polisher, Polishes 3.63 - 4.54kg of Rocks - Image 5](https://m.media-amazon.com/images/I/81fApJVQmeL.jpg) ## Available Options This product comes in different **Style** options. ## Questions & Answers **Q: How many oz is in each container?** A: 1 Coarse-16oz. 2 Medium-13oz. 3 Pre-polish-12oz. 4 Polish-11.5 oz. **Q: I just opened this and finished with grit one, went to put grit 2 in and bottle open and 1/2 full. How do I contact seller?** A: I would go through Amazon to get an answer for your problem. **Q: Can it be used together ?** A: Each grit is a different fineness intended for a specific purpose. We do not recommend using them at the same time. We do recommend 1 TBS grit per per 1 LB rocks, at each cycle. For further information please contact us at help@natgeotoys.com. **Q: After each step for the rocks in the kit, my rocks dry with a dull white finish. It doesn't show when it is wet. Am I doing something wrong?** A: No. I find that after tumbling with the finest grit after the last step... and thoroughly allowing the rocks to dry, a nice coat of wax or oil brings out the color beautifully. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Perfect Refill Set *by S***E on 29 May 2025* Perfect refill pack. More than enough quality materials to keep us tumbling rocks for many, many months. Great value and includes instructions, which was very handy as we misplaced the ones that came with the tumbler itself. ### ⭐⭐⭐⭐⭐ Perfect size for the rock tumbler! *by K***M on 17 October 2025* Exactly what I needed, more grit for my tumbler! I recently got some of my own beach rocks; quartz and serpentine, possibly some granite, and I needed these to tumble away! Good size, easy to use, functions as it should, measuring spoon and instructions made it easy to use. Think this is probably fun for kids, but definitely is for adults! ### ⭐⭐⭐⭐⭐ Rock tumbler *by A***R on 4 December 2025* Ideal hobby rock tumbler ## Frequently Bought Together - Blue Marble National Geographic Rock Tumbler Grit and Polish Refill Kit - Tumbling Grit Media, Polish Up to 20 lbs. of Rocks, Works with Any Rock Polisher, Rock Tumbler Supplies - 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 - UU UNIHOM 3 lbs Bulk Rough Madagascar Stones Mix Large 1" Natural Raw Stones Crystal for Tumbling, Cabbing, Fountain Rocks, Decoration,Polishing, Wire Wrapping, Wicca Reiki Crystal Healing --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.us/products/48271698-national-geographic-rock-tumbler-grit-1-49kg-polishing-grit-media](https://www.desertcart.us/products/48271698-national-geographic-rock-tumbler-grit-1-49kg-polishing-grit-media) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-07-23*