Lortone 3F 320/400 grit Silicon Carbide Fine Tumbling Medium 5 lb 591-082(19011)

"Tumbler grit" is a silicon carbide powder that is much harder than the types of rocks that are commonly tumbled. If it is tumbled in a barrel with rock and water the abrasion caused by the grit particles rounds the sharp edges off of the rocks. We use about four tablespoons of grit in a three-pound capacity tumbler barrel.

STEP 3 of the rock tumbling process prepares your rocks for polishing. This silicon carbide pre-polish removes scratches made by coarse and medium grit. It is a 320/400 mesh silicon carbide powder. In a rotary tumbler we use about four tablespoons of fine grit for every three pounds of barrel capacity.

Caution: Do not dispose of used grit, polish or rock slurry down a drain.