Pumice and rottenstone are natural light abrasives derived from limestone. They are recommended by professional refinishers and woodworkers for polishing varnished surfaces. Use these abrasives as the last step in finishing or refinishing a piece of furniture, or buff with pumice and rottenstone on a regular basis to maintain finished wood surfaces. Pumice and rottenstone are ground and sold in powder form. Your first step is buffing with pumice to remove imperfections and varnish brush strokes. Finish polishing the surface with rottenstone. The result is a lower-gloss, satin finish.
Things You'll Need
3 felt blocks
Powdered finest grade pumice (4F or FFFF)
Paraffin oil or water
Small plastic mixing vessel
Cotton work gloves
Soft, clean cloths
Furniture cleaner (optional)
Allow newly varnished wood to dry fully. Wear work gloves and face mask.
Wet the surface you are polishing with water or paraffin oil.
Sprinkle pumice onto the surface. Use a felt block to rub the pumice in the same direction as the wood grain with long, even strokes.
Keep the pumice moist by sprinkling additional water or oil onto the surface as necessary. Make sure to wet each section of the surface as you start working on it and before you sprinkle pumice and begin buffing.
Clean the surface with water or a furniture cleaner to remove the pumice. Wipe the surface dry with a soft, dry cloth.
Pour some rottenstone into a small mixing vessel. Saturate a fresh felt block with water or paraffin oil.
Dip the felt block into the vessel of rottenstone so that the bottom of the block is covered in the powder. Shake off any excess rottenstone that does not adhere to the block.
Rub the rottenstone into a small area using six to eight even strokes in the same direction as the grain of the wood.
Remove any excess rottenstone with a cloth soaked in water or oil, depending upon which you used to saturate your felt block. Use a clean, soft, dry cloth to dry the area you have polished.
Repeat Steps 7 through 9 until you have wet-polished the entire surface.
Lightly sprinkle rottenstone onto the surface for a final, dry rottenstone polish. Use a fresh felt block to rub it into the surface with long, even strokes in the same direction as the grain of the wood.
Remove any rottenstone dust from the surface with a clean, dry cloth. Clean the surface with a reliable furniture cleaner according to manufacturer's directions to remove any remaining dust, if necessary.
Water or oil can be used for buffing with rottenstone and pumice on most varnished surfaces. Water will produce a higher-gloss finish.
Do not use water for buffing if the surface is shellacked rather than varnished.