Do you have white deposits like the one below on the ceramic?
We can imagine that you are concerned about the white deposit. Do not panic! This is due to moisture that has been absorbed into the ceramic. This usually happens more often in the winter. You can brush away the white (limescale) deposits by treating it with natural vinegar. Then rinse or rinse it well with clean water. This can be applied to both the glossy and the urban version. Depending on the thickness of the white deposit, you may have to perform this treatment a (number of) times.