Natural stone sinks, wash basins and bathtubs are extremely easy to care for. Fact is that they are maintenance free! Only they need is a little care and they will give you a lifetime of service. Give your stone sink and Bathtub a periodic cleaning with a very mild soap and dry it with a soft, clean cloth. And it is recommended to apply high quality penetrating sealer every 3 -4 years that is appropriate to the type of stone your sink, wash basin or your bathtub is made of.