Polishing pads are hand-held cloth, leather, or felt blocks charged with fine abrasive compound, used for the localised finishing of gemstones and jewellery surfaces where machine polishing is impractical or unsafe. The pad takes the place of the rotating wheel; the abrasive does the same work, but more slowly and under direct manual control. Pads are the standard tool for the cabochon polisher's final pass, for stone-in-place touch-up on a finished setting, and for delicate work on engraved or matte surfaces that would be flattened by a buff.

Materials and charging

Felt pads, dense and slightly compressible, hold cerium oxide and aluminium oxide well and are the standard choice for cabochon work in quartz, agate, beryl, and feldspar. Leather pads, harder and more resistant to glazing, are preferred for high-Mohs material and for applications where a crisp facet edge must be preserved. Cloth pads, typically of muslin or chamois, are used with diamond paste or with rouge for fine work on metal and softer stones.

Pads are charged by working a small quantity of paste or slurry into the surface with the thumb or with a spatula, or by drawing a compound bar across the pad until the surface is loaded. The operator works the pad across the stone in short, overlapping strokes, refreshing the charge as the cut slows. A clean pad is reserved for each compound; cross-contamination between coarse and fine charges leaves visible scratches at the final stage.

Use cases

Polishing pads are essential for finishing cabochons after the dome has been shaped and pre-polished on the lap, particularly where the operator wants to preserve a soft girdle line that would be eroded by aggressive machine work. They are also used for hand-polishing engraved surfaces, where a wheel would round over the engraving lines, and for working stones-in-place — the final touch-up of a prong tip, a bezel edge, or a small facet on a stone already secured in its setting.

For soft or delicate stones, particularly turquoise, opal, and pearl, pads are often the only safe option, because the heat and pressure of a motorised wheel risk thermal shock or surface damage. The pad allows the operator to control both pressure and dwell time directly, and to back off instantly when the surface starts to take heat.

In the trade

The polishing pad is one of the small tools that distinguishes a finishing operator with thirty years on the bench from one with three. It does the work the motor cannot do, and it does it under the operator's direct sense of pressure and progress. A working bench will hold half a dozen pads, each dedicated to a single compound, all stored away from oil and dust so the abrasive surface remains clean for the next session.

Further reading

• International Gem Society — cabochon polishing
• GIA Gems & Gemology — finishing techniques
• GIA Gem Encyclopedia — gemstone finishing