Marble top has become dull due to limescale:Limescale residues are generally removed with slightly acidic products. These however are not recommended in the case of polished marble as even weak acids attack stone and remove its sheen. For cleaning tops dulled by the limescale found in water, use of a polish like FORMULA MARMO. Apply the product with a soft cloth, polishing it and rubbing until completely dry. It cleans, polishes and protects the material, slowing down its tendency.