Home >> Science & Nature >> Rocks & Minerals

How Do I Process Labradorite in the Rock Tumbler?

Labradorite, a feldspar mineral, is prized in jewelry-making as a semi-precious gemstone because of its "flash," or iridescent, in blue, green and red shades. This flash is best seen when labradorite is processed in a rock tumbler to smooth and polish its surface and highlight its coloration. In order to correctly tumble labradorite to its full potential, choose good quality, fracture-free "rough" stone and take your time moving between the different grades of polishing grit.

Things You'll Need

Safety glasses
Chunks of rough labradorite
Rock tumbler
Dish soap
Ceramic media
Polishing grits (coarse, medium, fine)
Colander
Plastic basin
Aluminum oxide powder
Ivory brand soap
Kitchen knife

Instructions

- 1
  Inspect the labradorite rough for cracks or fissures that will cause the rock to break during tumbling. Divide cracked rocks into smaller rocks.
- 2
  Wash the barrel of the tumbler thoroughly using warm water and a squirt of dish soap. Ensure that no grit is trapped under the rubber lip or rim.
- 3
  Place the labradorite rough into the barrel of the tumbler so the tumbler is approximately 3/4 full. If you don't have enough rough, add ceramic media until the barrel is 3/4 full.
- 4
  Add water to fill the barrel just below the top of the rough and top with 3 tbsp. of coarse grit. Seal barrel, place in tumbler and process for approximately 5 to 7 days.
- 5
  Open barrel and pour contents into a colander set over a plastic basin. Pick out the rough and clean the barrel again with water and soap.
- 6
  Place rough into the barrel of the tumbler so the tumbler is approximately 3/4 full. If you don't have enough rough, add ceramic media until the barrel is 3/4 full.
- 7
  Add water to fill the barrel just below the top of the rough and top with 3 tbsp. of medium grit. Seal barrel, place in tumbler and process for approximately 5 to 7 days.
- 8
  Open barrel and pour contents into a colander set over a plastic basin. Pick out the rough and clean the barrel again with water and soap.
- 9
  Place rough into the barrel of the tumbler so the tumbler is approximately 3/4 full. If you don't have enough rough, add ceramic media until the barrel is 3/4 full.
- 10
  Add water to fill the barrel just below the top of the rough and top with 3 tbsp. of fine grit. Seal barrel, place in tumbler and process for approximately 5 to 7 days.
- 11
  Open barrel and pour contents into a colander set over a plastic basin. Pick out the rough and clean the barrel again with water and soap.
- 12
  Place rough into the barrel of the tumbler so the tumbler is approximately 3/4 full. If you don't have enough rough, add ceramic media until the barrel is 3/4 full.
- 13
  Add water to fill the barrel just below the top of the rough and top with 3 tbsp. of aluminum oxide powder. Seal barrel, place in tumbler and process for approximately 5 to 7 days.
- 14
  Open barrel and pour contents into a colander set over a plastic basin. Pick out the rough and clean the barrel again with water and soap.
- 15
  Place the now-not-rough labradorite into the barrel with clean water and a few slices of Ivory brand soap (shave off slices using a kitchen knife). Seal and process for 24 to 48 hours to burnish the stones to a high shine.

Rocks & Minerals