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How to Use a Vibrator for Polishing Rocks

There are two common types of rock polishers, rotating tumblers and vibrating tumblers. Rotating tumblers take four to five weeks and produce smooth, rounded rocks. Vibrating tumblers take only a week and a half to two weeks and produce highly polished rocks that retain much of their original geological shape. The tumbler uses sand-sized pieces of silicon carbide grit, which is much harder than common rocks, to grind the rocks smooth. Tumbling grit comes in different levels of coarseness and is available at any geological hobby shop.

Things You'll Need

Vibrating rock tumbler
Various sized rocks, up to 1.5 inches in diameter
Tumbling grit
Water
Soap flakes

Instructions

The Initial Grind
- 1
  Fill the barrel of the tumbler 3/4 full with rocks. For every 4 lbs. of rock, add 3 tbsp. grit.
- 2
  Turn the tumbler on and begin adding water slowly until grit begins to cling to the stones. Do not overfill or grit will rinse away from the stones.
- 3
  Replace the tumbler lid. Check the tumbler at least twice a day for clumped buildup of grit and ground rock. Add water to thin it out.
- 4
  When you are satisfied with the shape and look of the rocks, usually after two to seven days, turn off the tumbler and thoroughly rinse grit from the rocks and bowl. Do not dispose of grit in a sink or drain.
Polish and Finish
- 5
  Return thoroughly rinsed rocks to the barrel. Follow the same steps as with the initial grind, except use half as much grit.
- 6
  After two to three days to pass then thoroughly rinse the rocks and barrel, removing all grit.
- 7
  Return the rinsed rocks to the barrel and repeat the steps for the initial grind, again using half as much grit as in the first grind.
- 8
  
  Rocks polished in a vibrating tumbler retain much of their natural shape.
  
  After two to three days remove and rinse the rocks and barrel once more. Return the rocks to the barrel with 1 tbsp. of soap flakes or detergent and run with water for a few hours for the final burnish.

Rocks & Minerals