# Best bulk rock tumbler grit: 10 lb to 40 lb packs by stage Source: https://tumblegrit.com/best/best-bulk-rock-tumbler-grit Publisher: Tumble Grit. Picks are chosen from what each Amazon listing states, not from hands-on tests. Method: https://tumblegrit.com/how-we-pick Buying grit in bulk pays off once you tumble regularly, because the 1 lb jars in starter kits cost several times more per pound than 10 lb tubs. Coarse grit runs out first: hard rough such as agate or jasper often needs two or three coarse runs before it moves on, so the step 1 grit goes several times faster than polish. Most instructions call for about 1 to 2 tablespoons of grit per pound of rock per stage. That makes a single-stage 10 lb tub of 60/90 a better first bulk buy than a balanced kit, unless you run large barrels. Things to check: the grading (60/90 for coarse, 120/220 or 180/220 for medium, 500 or 600 for pre-polish, aluminum oxide for polish), pure silicon carbide rather than a blend, and a resealable container, since damp grit clumps. This guide compares seven bulk packs. ## Picks ### 1. 40 lb Bulk Rock Tumbler Grit Refill - Polishing Media Kit A 40 lb bulk set: 10 lb of 60/90 and 10 lb of 120/220 silicon carbide, 8 lb of 500 silicon carbide, 8 lb of 1500 aluminum oxide, plus 3 lb ceramic filler and 1 lb polishing beads. What the listing offers: - Every stage in bulk, with the weight weighted toward coarse and medium as it should be - Listing states 99% pure silicon carbide and 99.5% aluminum oxide - Ceramic filler and polishing beads included for topping up light loads Limits to know: - Highest outlay in this guide, and too much grit for someone with a single small tumbler - 1500 aluminum oxide is a standard polish; some hobbyists prefer a finer final polish on quartz ### 2. 11 lbs Rock Tumbler Grit - Coarse 60 Silicon Carbide Tumbling Media, Step 1 for Tumbling Stones, Works with Any Rock Tumbler or Stone Polisher, Polish Up to 60 LBS of Rocks 11 lb of straight 60 grit silicon carbide for step 1, rated by the maker to process up to 60 lb of rock. A bulk coarse refill for hard rough that needs several coarse runs. What the listing offers: - 11 lb jar is a full year of coarse grit for most hobbyists with one or two barrels - 60 grit cuts fast on quartz, agate and jasper, which the listing names - Single jar from a tumbler brand, with a stated rock coverage figure Limits to know: - Straight 60 rather than graded 60/90, so it leaves slightly coarser scratches to remove in step 2 - Coarse only, so medium, pre-polish and polish must be bought separately ### 3. MJR Tumblers Rock Tumbler Grit Kit Refill for 10lb Tumblers, 4 Step Silicon Carbide & 12,000 Grit Aluminum Oxide Polish, Stone Polishing Kit for Rotary & Vibratory Rock Tumblers A 4-stage refill pre-measured for one run of a 10 lb tumbler: 60/90 coarse, 120/220 fine, 400/600 pre-polish and a 12,000 grit aluminum oxide polish. From a small US-based seller. What the listing offers: - Pre-measured for 10 lb barrels, so no guessing at amounts on a large tumbler - 12,000 grit aluminum oxide polish for a high final shine - Listed for rotary and vibratory tumblers Limits to know: - One run's worth for a 10 lb barrel, so the total weight is much lower than the 10 lb tubs - Not useful for a 3 lb barrel unless you split the packs yourself ### 4. 10 lbs Rock Tumbler Grit - Fine 1200-Grit Aluminum Oxide, Step 4 Final Polish for Tumbling Stones, Works with Any Rock Tumbler or Stone Polisher, Polish Up to 60 LBS of Rocks 10 lb of fine 1200 grit aluminum oxide sold as a step 4 polish, rated by the maker for up to 60 lb of rock. A bulk polish for hobbyists running many batches. What the listing offers: - Aluminum oxide polish in bulk, normally the most expensive grit per pound - Stated coverage of up to 60 lb of rock per jar - Listed as compatible with National Geographic, KoolStone and Lortone tumblers Limits to know: - Listing describes it both as the final polish and as a step before ultra-fine compounds, which is confusing - 1200 is a medium-fine polish; some stones need a finer final step for a glassy shine ### 5. 10 LBS Rock Tumbler Grit Set, Rock Tumbler Grit Refill Kit, Tumbling Media,4-Steps Supplies for Tumbling and Polishing Stones and Gems A 10 lb 4-step set: 2 lb coarse, 2 lb medium, 1.5 lb pre-polish and 1.5 lb final polish, plus 2 lb ceramic filler, 1 lb polishing beads and a spoon. What the listing offers: - Mid-size bulk kit that covers all four stages without committing to 40 lb - Ceramic filler and polishing beads in the set - Low price for the total weight, with a measuring spoon Limits to know: - Listing does not give the grit grading for each stage - 2 lb of coarse runs out quickly if your rough needs repeated step 1 runs ### 6. MJR Tumblers 60/90 Grit Silicon Carbide Rock Tumbler Grit, Extra Coarse Stage 1 Rock Polishing Grit, 20 lb Stone Polishing Compound for Rotary & Vibratory Tumblers, Lapidary Supply Grit: 60/90; Material: Silicon carbide; Weight: 20 lb; Container: not stated The largest pack in this guide: 20 lb of 60/90 silicon carbide for step 1. Suits large barrels, several tumblers, or a long run of repeated coarse cycles. What the listing offers: - The listing states 60/90 grit silicon carbide for the first stage of rock tumbling, in a 20 lb size. - Listed as compatible with most rock tumblers, including rotary and vibratory machines. - The product page says it can be used on stones, minerals and glass, including sea glass projects. Limits to know: - 20 lb is far more than one small 3 lb barrel is likely to use in a short time. - The spec sheet does not state the container type or how the 20 lb is packed. ### 7. YHAspace 10 lbs Tumbler Media Grit,Rock Polishing Grit Media, Works with Any Rock Tumbler, Rock Polisher, Stone Polisher,Medium 180/220 Silicon Carbide Grit, Step 2 for Tumbling Stones 10 lb of 180/220 graded silicon carbide for step 2. A bulk medium grit for tumblers whose coarse supply is already covered. What the listing offers: - Graded 180/220 is a standard step 2 size that follows 60/90 coarse cleanly - 10 lb lasts many runs, since medium is usually run once per batch - Compatible with any rotary tumbler brand Limits to know: - Sparse listing with no stated purity or coverage - Medium only, and many hobbyists use medium more slowly than coarse, so 10 lb may sit for years As an Amazon Associate I earn from qualifying purchases.