The removal of gold plating from jewellery is often desirable if the gold surface has become tarnished or lacklustre. In most cases it will not be possible to preserve the gold as it is removed. Gold plating is very thin, usually over a silver or copper base, and the process will typically destroy the thin layer of gold as it is removed.
Plating Preparation and Removal
Fill the glass jar or basin with denatured alcohol. Add three spoonfuls of the boric acid.
Put on gloves and glasses. Stir the boric acid/alcohol solution. Grip the piece of jewellery with the pliers.
Dip the jewellery in the boric acid/alcohol solution while the stirred solution is in motion. Remove the jewellery from the solution and move away from the jar or basin.
Heat the jewellery with the torch. The alcohol will burn off, leaving a white powder of boric acid. Remove the torch from the jewellery as soon as the flame is visible.
Make sure that the item is sufficiently coated with boric acid. If not, allow the item to cool completely and repeat steps 3 and 4.
Apply the torch again. The gold will quickly disappear.
If this technique is unsuccessful, the item of jewellery may have a thicker plating of gold and will require the use of a jeweller's buffing wheel, preferably coated with rotten stone, to remove the gold plating.
Keep flames and heated metal away from containers of denatured alcohol. The alcohol is flammable. Boric acid is not significantly more toxic than table salt. However, care should be taken that is it kept away from eyes and not ingested. Ensure that you are in a safe work space before beginning, with nothing flammable nearby or underfoot.