Dust, soap droplets and lime scale are responsible for the oxidation and deterioration process of this type of product. Use water and neutral soap for washing and a cotton cloth for drying for an effective cleaning operation. A toothbrush with soft bristles may be useful to clean small crevices.
The same process should be applied to pieces with gold or other finishes.
Abrasive products, like acids and other chemicals, are harmful and should be avoided on these types of surfaces. To remove difficult stains we recommend using of a lemon-based solution.