Ceramic sinks make beautiful bathroom, kitchen or mudroom fixtures, and they generally are quite durable. However, they occasionally will chip, usually as a result of a sharp collision with a heavy enamelled or cast iron pot. Fortunately, small nicks and chips in ceramic sinks can be repaired in just a few days--most of which is drying time.
Wash the chipped area in the ceramic sink thoroughly, using soap and water. Rinse the chipped area well, and allow the area to dry completely. Dry the repair area with a hair dryer to ensure that no absorbed moisture remains inside the ceramic material.
Dab a thin coat of oil-based primer/sealer into the chip, and allow the primer to dry for at least 2 hours.
Apply a coat of high-gloss oil paint over the primed repair area, and allow it to dry for at least 24 hours. Choose a paint colour that matches your sink as closely as possible. If you have the missing chip, take it to a speciality paint shop, where the colour can be matched exactly.
Mix a solution of two-part marine epoxy on a piece of cardboard scrap. Squirt equal amounts of each epoxy part onto the cardboard, and mix well with a toothpick.
Dab the epoxy into the chip, on top of the painted repair. Apply the epoxy slowly, dripping it into the chip with the toothpick. Fill the chip until the epoxy level matches the surrounding sink.
Allow the epoxy to dry for at least 24 hours before exposing the repair to moisture.
Always ensure adequate ventilation when working with oil-based paints and primers.