Gear guide
Best rock tumbler grit kits for a full 4-stage run
Picked from Amazon listings, not hands-on tests. How we pick
A rock tumbler grit kit puts all four steps in one purchase: coarse grit (step 1, 60/90), medium grit (step 2, 150/220), fine or pre-polish grit (step 3, 500 or 600) and polish (step 4, usually aluminum oxide). The kits differ in total weight, in how that weight is split between the steps, and in whether ceramic media or plastic pellets are packed in. The split matters most. Only step 1 changes the shape of the rock, and hard, jagged rough often needs 2 to 4 coarse runs, so coarse grit runs out first. A kit with equal coarse and medium jars leaves medium grit on the shelf, while a kit weighted toward step 1 is used up more evenly. A rotary barrel takes about 2 level tablespoons of grit per pound of rock in every step. This guide compares seven 4-step kits by what their listings state: the weight of each step, total weight, the amount of rock or barrel size the seller quotes, and the container. Nothing here was run in a tumbler, and the coverage figures are the sellers' own.
Compare the picks
| Pick | Steps | Total weight | Rocks or barrel stated | Container | Price | Per lb | Link |
|---|---|---|---|---|---|---|---|
 Polly Plastics 4-step grit and polish kit, 3 lb | 4 (1, 1, 0.5, 0.5 lb) | 3 lb | Up to 20 lb of rocks | Jars, all the same size | - | - | Amazon |
 YHAspace 4-step rock tumbler grit set, 12 lb | 4 (5, 4, 1.5, 1.5 lb) | 12 lb | not stated | Bottles | - | - | Amazon |
 KomeStone 4-step grit kit with dual media, 10 lb | 4 (2, 2, 1.5 lb + polish) | 10 lb with media | Up to 70 lb of rocks | not stated | - | - | Amazon |
 AtoRock 4-step grit kit with ceramic media, 4 lb | 4 (1, 1, 0.5, 0.5 lb) | 4 lb with ceramic media | Up to 25 lb of rocks | Individual bottles | - | - | Amazon |
 Kandylio 4-step rock tumbler grit kit, 4 lb | 4 (1 lb each) | 4 lb | Up to 30 lb of rocks | Jars, all the same size | - | - | Amazon |
 National Geographic grit and polish refill kit | - | - | - | - | - | - | Amazon |
 MJR Tumblers grit kit refill for 3 lb tumblers | 4 (pre-measured) | not stated | Pre-measured, 3 lb tumbler | not stated | - | - | Amazon |
Facts are taken from each Amazon listing. Prices are checked daily and shown with their date.
If you just want one
- Closest match for the jobPolly Plastics 4-step grit and polish kit, 3 lbThe listing gives the grade and weight of every step: 60/90, 180/220 and 500 silicon carbide, then 1200 aluminum oxide polish.
- Most for the money on paperYHAspace 4-step rock tumbler grit set, 12 lbStep 1 gets the largest share, 5 lb of 60/90 coarse silicon carbide, which matches the step that is repeated most often.
- Most complete listingKomeStone 4-step grit kit with dual media, 10 lbCeramic tumbling media and plastic pellets are both in the box, so no separate filler purchase is needed.
The picks in detail
Pick 1 · Polly Plastics
Polly Plastics 4-step grit and polish kit, 3 lb
See price on AmazonA grit-only 4-step kit: 1 lb each of 60/90 coarse and 180/220 medium silicon carbide, 1/2 lb of 500 fine silicon carbide and 1/2 lb of 1200 aluminum oxide polish. It suits small rotary barrels and anyone who already owns media.
What the listing offers
- The listing gives the grade and weight of every step: 60/90, 180/220 and 500 silicon carbide, then 1200 aluminum oxide polish.
- Instructions with rock tumbling tips are included, and the listing states the kit is made in the USA.
- Sold as universal grit for any rock tumbler, with a stated coverage of up to 20 lb of rocks from the 3 lb pack.
Limits to know
- Coarse and medium grit are both 1 lb, so repeated step 1 runs on hard rough will empty the coarse jar first.
- No ceramic media or plastic pellets in this version, and the step 3 and 4 jars hold 1/2 lb each in full-size jars, so they arrive partly filled.
Pick 2 · YHAspace
YHAspace 4-step rock tumbler grit set, 12 lb
See price on AmazonA bulk 4-step set weighted toward the early steps: 5 lb of 60/90 coarse, 4 lb of 180/220 medium and 1.5 lb of 500 fine silicon carbide, plus 1.5 lb of 1500 aluminum oxide polish. It suits larger barrels and repeated step 1 runs.
What the listing offers
- Step 1 gets the largest share, 5 lb of 60/90 coarse silicon carbide, which matches the step that is repeated most often.
- The listing states purity figures: 99% for the silicon carbide and 99.5% for the aluminum oxide polish.
- Each of the four steps is packaged in its own bottle, described as easy to use and store.
Limits to know
- The listing gives no figure for how many pounds of rock or how many batches the 12 lb covers.
- No ceramic media, plastic pellets, scoop or instructions are mentioned, and 12 lb is a lot of grit for a 1 lb kit tumbler.
Pick 3 · KomeStone
KomeStone 4-step grit kit with dual media, 10 lb
See price on AmazonA large kit that adds both kinds of filler: 2 lb of 60-grit coarse and 2 lb of 150-grit medium silicon carbide, 1.5 lb of 600-grit fine, the step 4 polish, plus ceramic media and plastic pellets. Aimed at frequent tumbling and larger barrels.
What the listing offers
- Ceramic tumbling media and plastic pellets are both in the box, so no separate filler purchase is needed.
- The listing quotes up to 70 lb of rocks across multiple batches from the 10 lb kit.
- Stated as compatible with rotary and vibratory tumblers from all major brands.
Limits to know
- The 10 lb total includes the ceramic media and plastic pellets, so the grit itself weighs less than the headline figure.
- Coarse and medium are equal at 2 lb each, so the coarse grit will run out first when step 1 has to be repeated.
Pick 4 · AtoRock
AtoRock 4-step grit kit with ceramic media, 4 lb
See price on AmazonA 4 lb kit with 1 lb of 60-grit coarse, 1 lb of 150-grit medium and 0.5 lb of 600-grit fine silicon carbide, 0.5 lb of 1200-grit aluminum oxide polish, and ceramic tumbling media. A fit for a first refill when no filler is on hand.
What the listing offers
- Ceramic tumbling media is included with the four grits, so an under-filled barrel can be topped up from the same box.
- The listing gives a dose: 2 spoons of grit for every 1 lb of rock in each stage, 4 spoons for 2 lb.
- Each grit comes in its own bottle, and the kit is stated as compatible with rotary and vibratory tumblers.
Limits to know
- Only 3 lb of the 4 lb is grit, split 1, 1, 0.5 and 0.5 lb, the same coarse share as smaller grit-only kits.
- The step 3 and step 4 bottles are only partly filled, which the listing puts down to consistent packaging.
Pick 5 · Kandylio
Kandylio 4-step rock tumbler grit kit, 4 lb
See price on AmazonFour 1 lb jars: 60-grit coarse, 220-grit medium and 500-grit fine silicon carbide, plus 1200-grit aluminum oxide polish. The full pound of step 3 and step 4 suits anyone who runs short of pre-polish and polish with 3 lb kits.
What the listing offers
- A full 1 lb of 500 fine grit and 1 lb of 1200 aluminum oxide polish, double the step 3 and 4 amounts of the 3 lb kits here.
- The listing names the grade and weight of each jar and quotes up to 30 lb of rocks for the kit.
- Described as working with all brands of rock tumblers for kids and adults.
Limits to know
- Equal weights mean the coarse jar empties long before the polish, since step 1 is the one that gets repeated.
- Coarse and medium are given as single numbers (60 and 220), no media is included, and instructions are not mentioned.
Pick 6 · Blue Marble
National Geographic grit and polish refill kit
See price on AmazonThe branded 4-step refill sold for the National Geographic kit tumblers. The listing says the silicon carbide grit polishes up to 20 lb of rocks and works with all rock tumblers; weights and grades are not given.
What the listing offers
- Four stages in one pack: initial shaping, smoothing, pre-polish and final polish, each in its own container.
- Each stage is packaged in a wide-mouth container with a screw-top closure for measuring and storage.
- Stated to work with all rock tumblers and to cover up to 20 lb of rocks, gems, glass and more.
Limits to know
- The listing does not state the weight of the kit or of any step, so it cannot be compared pound for pound.
- Grit grades and the polish type are not given, and no media, scoop or instructions are mentioned.
Pick 7 · MJR Tumblers
MJR Tumblers grit kit refill for 3 lb tumblers
See price on AmazonA pre-measured refill for 3 lb tumblers: 60/90 coarse, 120/220 and 400/600 silicon carbide, then a 12,000 grit aluminum oxide polish. The contents of each stage go in whole, so there is nothing to measure.
What the listing offers
- Each stage is pre-measured for a 3 lb tumbler: add the contents at each step, with no scoop or scale needed.
- The listing names every grade: 60/90, 120/220 and 400/600 silicon carbide and 12,000 grit aluminum oxide polish.
- Stated to work with rotary and vibratory tumblers, from a USA-based, veteran-owned brand.
Limits to know
- The weight of each portion is not stated, and the listing does not say how many loads the kit covers.
- No spare coarse grit for a repeated step 1 run, and no media or pellets in this version of the kit.
Read before you buy
- Rock tumbling quartz: grit schedule and how to avoid chipped edgesQuartz tumbling recipe: grit and time for each step, how much ceramic media stops chipped and frosted edges, and how quartzite differs.
- Rock tumbling agates: grit, times and common problemsAgate tumbling schedule start to finish: grit and amount for each step, 5 to 8 weeks in total, plus fixes for pits, fractures and dull bands.
- Rotary vs vibratory rock tumbler: differences and which to chooseRotary vs vibratory rock tumbler compared: shaping, 7 days vs 2 to 3 days per step, grit use, noise and cost, plus how to run a vibratory bowl.
- Best rocks for tumbling: hardness chart and rocks to avoidHardness chart for 20 common tumbling rocks: Mohs value, whether each one polishes, which rocks can share a barrel and which to skip.
- Rock tumbling grit chart: grit size, amount and time for each stageRock tumbling grit chart for all four steps: grit size, what each step does, days per step and how to tell it is done, plus about 2 tbsp of grit per pound.
More gear for the loading the barrel stage
Tumble Grit chooses every product independently from what its Amazon listing states. We may earn a commission from the links above. As an Amazon Associate I earn from qualifying purchases.