Ordinary gold jewelry may be effectually cleansed by washing with soap and warm water, rinsing in cold water and drying in warm boxwood sawdust. Plain, smooth surfaces may be rubbed with chamois leather charged either with rouge or prepared chalk, but the less rubbing the better.
Silver is liable to tarnish by the action of sulphur, and where there is fine chased or engraved work the extreme delicacy of the lines may be injured by much rubbing. In such cases the articles may be cleaned by washing with a solution of hyposulphite of soda. Cyanide of potassium is a more powerful cleansing agent but is very poisonous.
In cleaning gilded ware, different processes must be used for articles gilded by fire or by the galvanic process, and articles gilded by gold leaf, such as frames, etc. For cleaning articles gilded by the first-named methods, one part of borax is dissolved in sixteen parts of water. With this solution the article is carefully rubbed by means of a soft sponge or brush, then rinsed with water, and finally dried with a linen rag, or if small, such as a piece of jewelry, with boxwood sawdust. If at all convenient, the article is warmed previously to being rubbed, by which means the brilliancy of it is greatly increased. In cleaning gilded frames of the last named order, pure water only must be employed, and the rubbing off of the impurities must take place by means of a very slight pressure. Wares of imitation gilt are generally covered with a shellac or resin varnish, which would be dissolved by the application of soap water, alkaline solutions, or spirits of wine. Were the varnish rubbed off, the exceedingly thin layer of gold or silver leaf beneath would also disappear. In our experience we have seen hundreds of once valuable but now worthless frames, they having become thus simply by the application of soap water.