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Any Piece of Jade Will Take a Polish

Jade varies from piece to piece in characteristics that affect grinding and polishing. If one system fails a person must try alternatives that eventually will result in a creditable polish.

Grind and polish as you would an agate. Remember jade is softer and more fibrous than agate. Take the following precautions:

Trim saw your piece out of the slab without pushing. Take your time. If you try to rush the sawing you may start small edge fractures that will show up in the final stone.

Grind to size using plenty of water. Don't push too hard or you may get a "white spot" or spread the edge fractures.

Grind to shape using a steady turning of the stone on the wheel so that you are taking off the unwanted material without danger of enlarging any small edge fractures. Don't zip back and forth. Be on the lookout for potential hard spots. If they show up, carefully take them down.

220 sand with uniform strokes-steady but light. Check frequently. The grinding marks will disappear quickly. The shaping of the stone is the main thing.

320 sand -the hard spots if any will start to show.

400 sand - work the hard spots down. Finish sanding lightly and complete the shape.

600 sand - light steady pressure.

Polish on leather disk. First clean off the buff with a wad of wet paper toweling and squirt water on at the same time. Get rid of all the old tin oxide and crud that you possibly can. Polish the stone on the leather near the center of the disk. In other words, use slow speed. Use a squirt of water on the buff. Put a little dab of tin oxide on your stone-not on the buff. When the buff starts to dry you will get the best pulling action. You can use pressure but get the pulling action. Jade takes much longer to polish than agate. Don't give up! Don’t let the polishing disk get completely dry - the stone will burn or streak. If the stone winds up having irregular marks, orange peels, lumps, hard streaks, you will have to try something else. The best alternative is a system of hand finishing.

HAND FINISHING

Go back to the 400 grit and try to get a good looking shape and contour. Maybe you will have to go to 320 if it is an old wheel - then to hand finishing.

Alternatively - use the hand finishing sequence. This requires "wet-or-dry" sandpaper. It may be available in hardware stores, lumber yards or home improvement centers. It is always available in stores that have materials and equipment for the auto body repair trade.

Get 320, 400, 600, 1200 (or ultra fine). Cut the sheets (or fold and tear) to 1/8 size (2-3/4" x 4 1/4"). This size fits comfortably in your hand. Also you should have a flat piece of wood (paint paddle) about 5" long. Leave your stone on the dipstick. To remove streaks or lumps lay a piece of 320 on your stick.

(Better yet, glue the sandpaper on the stick and use as a file). Hang on to the paper and stick with one hand. Wet the stone. (You need a cup or small container of water) Dip your stone in water and precisely and carefully sand off the high spots. Actually sand them slightly below the surrounding surface.

Take the 320 paper in your hand Wet the stone. Sand the stone by turning the paper in the palm of your hand. With a bit of trial and error you can get a good contour.

Go to 400, 600 and finally 1200 in hour hand. Be careful not to re-create the streaks, lumps, etc. By 1200 the stone should have almost a polished look.

Use a piece of leather to polish by hand. I have an old leather from a dining room chair seat. Use the "inside" of the leather.

Again, put the leather over your hand; put a dab of tin oxide on it. Wet your stone and rub it on the leather. As the leather dries you will feel the pulling action. Keep at it.

Obviously this is slower than a machine buff but you will get good results.

Alternatively you can try your powered leather disk with light pressure with little tin oxide and quite dry. (To avoid speed stay close to the center of the wheel and keep the surface slightly damp. Do not let it dry out.)

Tom Leedham, Richmond Gem & Mineral Club 1/2004