How can you tell porcelain from ceramic?
Porcelain tiles have a fine-grained finish that is smoother than the finish on ceramic tiles. So, if the finish is slightly bumpy or coarse when you touch it, you're dealing with non-porcelain (ceramic) tile. If the tiles are already glazed, flip them over and look at the unglazed underside. How can you tell the difference between ceramic and porcelain pottery? Ceramic is opaque whereas porcelain is translucent. Porcelain has a fine and smooth surface, which is said to resemble the smoothness of an eggshell, and the material is thinner than ceramics.