All that is needed to clean your ceramic butlers sink is a soft, damp, soapy cloth.
Metallic abrasions from pots, woks and cutlery from fruit juices and tea can generally be wiped off using a scouring liquid and soft cloth. Problem spots can be treated with methylated spirits and rinsed using warm soapy waster and a soft cloth.
Warm vinegar can treat lime scale. Soak the area for 20 minutes, rinse well with warm water and finish off with warm soapy water and a soft cloth. More than one application may be required.
Avoid using cleaners containing solvents like formic acid or citric acid. Never spray oven cleaner or use a drain cleaner directly on the surface of the sink.
Never place anything hot directly onto the surface of the sink as a white bloom could result from the heat.