cabmaking6

How To Make a Cabochon, page 6
by Paul W. Cinnamon

STEP #15      FINAL POLISH
       The cabochon is now ready for a final polish. The polish pad and type of polish used is usually dictated by the kind of rock from which the cabochon is made. Most agates and jaspers are polished on a hard felt or leather pad using cerium oxide or tin oxide polish. A few of the other common pads and polishes are, canvas charged with 50,000 diamond, Fabuluster, Zam, chrome oxide, and Linde A. When in doubt about the proper polishing procedure for a particular material, I usually consult the book "GEM CUTTING", by John Sinkankas. Before installing or using a polish lap it is best to wash the cab, dopstick, and your hands to remove any minute particles of rock, diamond, or any other contaminant that might be carried over to your polish lap. Pay particular attention to the dirt and rock debris under your fingernails. I keep my polish laps in zip lock type bags, or at least covered when not in use. For my large 12 inch polishing lap, when not in use I keep it covered with the same type hairnet covering worn by surgery personnel in the operating room.
     The majority of cabbing material will take a good polish with Cerium Oxide, Tin Oxide, or Linde A. These all come in a power form and must be mixed to the proper consistency before use. I mix the polish with distilled water in a clean baby food jar. For mixing, I use a small plastic spoon that places like Sam's Wholesale use to pass out food samples to their customers. These spoons are small and short enough to be left inside the jar with the lid screwed on. A small amount of polish will go a long way. Mix one or two spoons of the powder with a small amount of water until it is the consistency of thick cream. Slightly moisten the nap of the polish lap, and using the spoon or your clean fingertip, smear a small amount of polish into the nap. This can sometimes be best done with the lap rotating slowly. In most cases, I polish at slow to moderate speed.
     Holding the dop securely with your fingers in contact with the back of the cab, so you can feel the heat build-up and/or the wax beginning to soften with heat, bring the cab in contact with the lap. Slowly apply pressure as you rotate and rock the cab from side to side moving it randomly about the face of the rotating lap. The best polishing action takes place just at the time when you feel maximum drag from the contact between the cab and the drying lap. If the lap becomes too dry, spray a bit of distilled water or add a bit of polish compound. Remove the cab from contact if you feel it becoming hot, or the wax is beginning to loosen. Be careful of the way you introduce the girdle edge to the lap surface so that you don't cut the lap, or break the cab. Some materials are quite heat sensitive, such as obsidian. With these you must take special care not to allow heat to build to a point where the cab will crack or break.
     After completely polishing the surface of the cab, clean off the polish residue and inspect.

STEP #16: REMOVING YOUR COMPLETED CAB FROM THE DOP STICK
     Your cabochon is now completed and may be easily removed from the dop stick by placing it in ice water or the freezer for 3 to 5 minutes. Unless you desire to polish the back of the cabochon, it is now ready to be mounted in a jewelry finding to be worn and enjoyed for many generations to come.