Tumbling will smooth the rough garnets.
Tumbling your rough garnets is a simple but time consuming task that will turn the rough rocks into polished gems. The unpolished raw garnet stones are called "tumbling rough." (See Reference 1) Before you begin, check the quality of your tumbling rough. (See Reference 1) Make sure all the rocks are the same material. It is acceptable to tumble rocks of various sizes together, but remove any stones that have big cracks or voids, or odd protrusions. (See Reference 2)
Instructions
Tumbling Garnet
1. Tumbled garnet can be used for jewelry.
Coarse grind your garnet. The coarse grind step is meant for rocks with jagged edges. (See Reference 1) If your garnet has been pre-tumbled or is slightly rounded or smooth from water erosion, you can skip this step. Put the tumbling rough into the rock tumbler barrel. Remember that the tumbler barrel must be more than half full (of water, grit and rough) to work correctly. Don't overload your barrel. It should not be more than about 75 percent full, because this can be too heavy for the tumbler motor to move. Follow your specific rock tumbler instructions regarding the coarseness of the grit used. Tumble the garnet for seven days, 24 hours a day. (See Reference 1)
2. Stop the tumbler and remove the "mud" and rocks. Don't put the mud down your household drain, as this can block your plumbing. (See Reference 1) Rinse the garnet outside using a strainer and a hose. If you don't like the shape of your stones, you can repeat this coarse grinding step at least one more time (See Reference 3) to continue to shape the rocks. Remember to use fresh grit every time you tumble.
3. Proceed to the fine grinding. Clean your tumbler thoroughly, put the pre-tumbled rock into the barrel, and use a finer grit than before. Again, check your specific rock tumbling machine's instructions to select which grit to use. Let the tumbler run continuously for another seven straight days. (See Reference 1) Process several loads of garnet before moving on to the pre-polish step, or you will not have enough material for your tumbler.
4. Proceed to extra fine grinding (also known as pre-polishing). (See Reference 1) Clean the tumbler barrel very thoroughly before starting this phase, or you will scratch your garnet. Use extra-fine grit for this step. You can also add plastic tumbling pellets, which help cushion the gemstones. (See Reference 1) Once again run your tumbler for a week straight.
5. Run the polishing load. Clean the tumbling machine as before and use rock polish this time instead of grit. (See Reference 1) Most people use plastic pellets for cushioning during this step as well. This time run your machine for ten days.
6. Finally, burnish your newly polished garnet. (See Reference 1) Clean the tumbling machine well and add a little bit of soap to the barrel. According to Geology.com, grated or thinly sliced Classic Ivory Soap is ideal. (See Reference 1) Do not use liquid soaps, as they may contain oils that can damage your machine and make your rocks look dull. Run your machine for a day or two to burnish the garnet. When done, you'll find a mess of sudsy water and a load of sparkling, polished gemstones.
Tags: this step, tumbler barrel, tumbling machine, tumbling rough, your garnet, your machine, your tumbler
