I do not believe that ceramic or tiles in general are a good idea. Using these you will have a cold surface and cats do not really appreciate that. For my two cats I have chosen laminate floors, they provide a warm feeling and are also scratch and moisture resistant. I have bought mine from here
www.pagerank10.co.uk/household/flo... , as the floors they have come in hygienic and anti-static treated surface, resulting in an easy to clean and safe for children and pets floor.