Gear guide
Best plastic pellets for rock tumbling and when to use them
Picked from Amazon listings, not hands-on tests. How we pick
Plastic pellets are light cushioning media. They go into the barrel with fragile or brittle stones, such as obsidian or glass, and into the polish step, where they soften the knocks that chip and bruise a load. They also help bring an under-filled barrel up toward the usual 2/3 full. Two properties set them apart from ceramic media. Pellets float, so they can be skimmed off the rinse water. And grit embeds in the plastic, so a batch of pellets must only ever be reused in the same grit step: keep one labeled batch per step and never move pellets from a coarse run into polish. Count pellets as rock when measuring grit. Dedicated pellet packs are few, and they differ mainly in weight, the plastic named in the listing and the bag. This guide compares four pellet packs and one 4-step grit kit that ships with pellets, using only what the listings state. No listing gives a pellet size, and nothing here was run in a tumbler.
Compare the picks
| Pick | Weight | Material | Packaging | Price | Per lb | Link |
|---|---|---|---|---|---|---|
 Tonmp plastic pellets tumbling media, 3 lb | 3 lb | Polypropylene | Re-closable seal bags | - | - | Amazon |
 Roly Poly plastic pellets tumbling media, 3 lb | 3 lb | Virgin plastic, USA made | Resealable heavy-duty bag | - | - | Amazon |
 Tonmp plastic pellets tumbling media, 2 lb | 2 lb | Polypropylene | Re-closable seal bags | - | - | Amazon |
 SACKORANGE plastic pellets tumbling media, 2 lb | 2 lb | Polypropylene | Re-closable seal bags | - | - | Amazon |
 Polly Plastics grit kit with 1 lb plastic pellets | 1 lb pellets + 3 lb grit | Polypropylene | Same-size jars for grit | - | - | 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 jobTonmp plastic pellets tumbling media, 3 lbThe material is named: impact-resistant polypropylene, stated to cushion the impact of stones.
- Most for the money on paperTonmp plastic pellets tumbling media, 2 lbA smaller 2 lb pack of the same impact-resistant polypropylene pellets as the 3 lb size.
- Most complete listingRoly Poly plastic pellets tumbling media, 3 lbThe listing states the pellets are manufactured in the USA from virgin material and are non-toxic.
The picks in detail
Pick 1 · Tonmp
Tonmp plastic pellets tumbling media, 3 lb
See price on AmazonThree pounds of impact-resistant polypropylene pellets in re-closable bags. Enough to set aside separate batches for different grit steps or to cushion a larger barrel of fragile stones.
What the listing offers
- The material is named: impact-resistant polypropylene, stated to cushion the impact of stones.
- Described as non-toxic, non-static and non-residue, and dryable for reuse.
- Packaged in durable, re-closable seal bags to prevent spills and for storage.
Limits to know
- No pellet size or shape is stated in the listing.
- The listing does not mention keeping batches separate per grit step, which pellets need because grit embeds in them.
Pick 2 · Roly Poly
Roly Poly plastic pellets tumbling media, 3 lb
See price on AmazonA 3 lb bag of plastic pellets made in the USA from virgin material. The listing says they suit all tumbling stages; since grit embeds in plastic, keep a separate batch for each step.
What the listing offers
- The listing states the pellets are manufactured in the USA from virgin material and are non-toxic.
- Pellets float to the surface, which the listing says makes them simple to skim off and reuse.
- Comes in a resealable heavy-duty bag for storage between uses.
Limits to know
- The type of plastic is not named and no pellet size is given.
- One 3 lb bag has to be divided by hand into separate batches for each grit step.
Pick 3 · Tonmp
Tonmp plastic pellets tumbling media, 2 lb
See price on AmazonThe 2 lb size of the same polypropylene pellets. A smaller amount for a 1 lb to 3 lb barrel where pellets are only needed in the polish step or for one fragile load.
What the listing offers
- A smaller 2 lb pack of the same impact-resistant polypropylene pellets as the 3 lb size.
- The listing says the pellets float to the top for easy cleaning and are easy to reuse.
- Re-closable seal bags are stated, to prevent spills and to store the pellets safely.
Limits to know
- Two pounds leaves less to divide into separate per-step batches than the 3 lb pack.
- No pellet size is stated, and the listing has no guidance on how much to add.
Pick 4 · SACKORANGE
SACKORANGE plastic pellets tumbling media, 2 lb
See price on AmazonA 2 lb pack of polypropylene pellets from another brand, with the same stated properties: non-toxic, non-static, dryable and floating. An alternative 2 lb option that the title lists for all types of tumblers.
What the listing offers
- Impact-resistant polypropylene is named as the material in the listing.
- Stated as non-toxic, non-static and non-residue, and dryable between uses.
- The title lists it for all types of tumblers, to protect fragile stones.
Limits to know
- The listing text matches other pellet listings almost word for word and adds no detail of its own.
- No pellet size is given, and the listing offers no usage amounts or instructions.
Pick 5 · Polly Plastics
Polly Plastics grit kit with 1 lb plastic pellets
See price on AmazonA 4-step grit kit that includes 1 lb of high-impact polypropylene filler pellets with 3 lb of grit and polish. It fits a buyer who needs grit anyway and wants pellets in the same order.
What the listing offers
- Includes 1 lb of high-impact polypropylene plastic filler pellets, stated to protect and cushion.
- The listing sizes the kit for use in a 15 lb tumbler or five 3 lb tumbles.
- Grit grades and weights are stated: 1 lb 60/90, 1 lb 180/220, 1/2 lb 500 and 1/2 lb 1200 aluminum oxide polish.
Limits to know
- Only 1 lb of pellets, so there is little to split into separate batches for each grit step.
- Most of the pack is grit; a buyer who only needs pellets is buying a full grit kit as well.
Read before you buy
- Why your tumbled rocks are not shiny and how to fix each causeNine causes of dull tumbled rocks, matched to what you see on the stone, with the grit step to go back to and the fix for haze, scratches and bruises.
- 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 Petoskey stones and other soft rocksPetoskey stone is calcite, about Mohs 3, too soft for the standard recipe. Hand sanding with 220 to 600 grit is usual. A short tumbler schedule if you tumble.
- Rock tumbling obsidian: cushioning, grit and timingObsidian is brittle volcanic glass at Mohs 5 to 5.5. Gentle schedule: barrel 2/3 to 3/4 full, 30 to 50% media, short coarse run, no white bruises.
- 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.
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.