Home >> Science & Nature >> Rocks & Minerals

How to Break Rocks for Tumbling

To tumble rocks, you need to place small pieces of rock are put into a tumbling barrel, along with polishing grit and water. This is then rotated by machine until the rocks end up looking smooth and polished. Most tumbling machines won't accept large pieces of rock, so it may be necessary to break up large stones. Creating smaller stones is often a matter of personal preference or so that they can be used for jewelry and craft projects. With a little bit of care and effort you can turn big rocks into smaller ones better suited for use in a rock tumbler.

Things You'll Need

Hammer, small sledge hammer or rock hammer
Heavy canvas bag
Eye protection
Leather work gloves

Instructions

- 1
  Place the larger rocks in the bag. Close or fold the end so that pieces cannot fly out when you are breaking them. You can do several rocks at once, or you can do one rock at a time.
- 2
  Set the rock bag on a hard surface that cannot be hurt by the force of the hammer or the rocks. Add a board under the bag for extra protection.
- 3
  Arrange the rocks in a single layer in the bag. If you are working with one or two rocks, place them with the flattest side down.
- 4
  Hit the rocks firmly with the hammer. Don't use all your strength on them, as you may not need to hit them as hard as you think. If you hit them too hard you might pulverize and destroy them.
- 5
  Continue to strike the rocks firmly until they are broken into the sizes you want. If you have more to do, remove the crushed rocks from the bag and add more. Rocks that are the right size can go directly into the tumbler.

Rocks & Minerals