HOW TO RESTORE MARBLE
fore you start make sure that you are actually working with marble, as there are many similar materials, e.g. alabaster or painted plaster. If in doubt, do not clean because the materials discussed below are not necessarily appropriate for imitation marble. Examine your piece in good light to establish if there are any potential problems. Look for evidence of a coating and traces of original paint or gilding. If you find any, clean around them without touching them.
Types of marble
Marble is a metamorphic rock. It is formed from limestone that has gone through a process of recrystallisation through heat or pressure. This gives it a dense crystalline structure that makes a polished surface possible. Marble can vary in colour from the whites and creams of classical sculpture to pinks, greens, greys, browns and yellows. These variations are a result of mineral impurities in the original limestone.
In the decorative arts, marble is commonly associated with statuary, but is also found in a variety of objects from furniture and clocks to light fittings and lampshades. In the home, marble is used for used for fireplaces and flooring due to its strength and durability.
Marble, like all stone, is both heavy and brittle. When these factors are combined with poor handling or internal weakness, the marble is liable to break. Whilst smaller objects may be made in a single piece, it is not uncommon for statuary to be made in multiple pieces. This may be as simple as a bust on a socle (a separate base or plinth), as complex as a large sculpture where arms and legs have been jointed on a torso, or a result of past repairs that have been dowelled into place