Barrel & Grit field manual
Ceramic media vs plastic pellets for rock tumbling
Ceramic media improves contact and stays in the working mass. Plastic pellets cushion more, float for separation and must remain dedicated to one stage.
Choose ceramic media for grinding contact
Ceramic shapes carry grit through the barrel, fill gaps between larger stones and help maintain a smooth rolling action. They are useful from coarse through polish when the same pieces are thoroughly cleaned between stages.
Choose plastic pellets for cushioning
Plastic pellets reduce hard impacts around delicate or already-rounded stones. Because they float, they are easy to skim off—but embedded grit makes them unsuitable for moving from one abrasive stage to another.
Do not use filler to rescue an incompatible batch
Media improves barrel fill; it does not make soft stones compatible with hard agate. Sort by hardness and condition first, then add only enough media to reach the working fill zone.
Store every stage separately
Label containers for coarse, medium, fine and polish media. That small habit is cheaper than repeating a contaminated final stage.