Great care must be taken with gilt furniture and mirrors. There are two types of gilding, water and oil. Water gilding appears more yellow in tone than the deeper orange appearance of oil gilding. Most English 18th and early 19th century furniture was water gilded although oil gilding was favoured with continental furniture. Layers of gesso were applied to the carved wooden base and then recut to define the carved decoration. A liquid clay base, or bole, was then applied and gold leaf laid upon it. With oil gilding, the gesso was applied with an oil size to which the gold leaf was then stuck. It is not a good idea to try and clean gilt, should water be applied to it the gold will wash off and expose the bole beneath.
Gilding restoration is best carried out by an experienced gilder and as the finish can vary the final look is best discussed with the gilder in question. Gesso is plaster based and therefore highly susceptible to water and moisture damage. Once the gesso becomes damp it will perish and the piece of furniture will have to be both regessoed and thus regilded. Do not hang gessoed mirrors on damp walls, in bathrooms or in rooms with a high degree of humidity. When dusting elaborately carved gilt furniture use a light feather duster rather than a cloth to avoid breaking off pieces of decoration and gilt. With painted furniture a damp cloth can be used, but never solvents. Afterwards a light coat of clear wax should be applied, but pay attention to any flaking decoration.
This is not exhaustive and if you are at all unsure please contact us!