I need to know what kinds of tiles (ceramic or procelin or others) would be more appropriate on walls, ceiling and floor of a shower 36 X 36 inches floor in a condo with concrete floors.

At least one advice given to me from a tile dealer is procelin is better than ceramic tiles for floor as well as walls. I am told that ceramic tiles absorbs moister but procelin tiles do not absorb moister.

My next question is whether my choice of 6 X 6 inches procelin tiles can be used on floor to maintain the required slope for drainage or it will cause problems.

I am giving the job to a tile contractor but I need answers to these two questions from independent source.