The process used by jewellers, of making metal smooth and glossy, after the piece has been fashioned and rubbed with any of various abrasives to give it its preliminary finishing. The polishing is done first by machine, using a polishing lathe fitted with various polishing brushes charged with emery powder and oil or with tripoli, and then by lathe or hand, using a polishing mop charged with tripoli, or rouge, after which the piece is completed by buffing with a buff stick. Small areas are polished by burnishing. Polishing the interior of a finger ring is done with either a felt cone attached to the spindle on the lathe or a ring-stick.
The polishing of gemstones is done on a rotating wheel (scaife) charged with various powders, including tripoli, putty powder, diatomite, rottenstone, and pumice. It is sometimes followed by an acid bath. A diamond requires no special polishing, as the stone, having no Beilby layer, is polished in the same operation as the faceting.
From: An Illustrated Dictionary of Jewelry, autor: Harold Newman, publishers: Thames and Hudson