Natural stone tiles are created by cutting through blocks of stone quarried straight from the earth, meaning they are made of the same natural material throughout. Even if they become chipped and when they are finished to look aged, the same colour and texture still exists on the surface.
Most ceramic tiles are made from clay that is shaped and then fired in a very hot kiln. Colours and decorative glazes are added as a top layer, sometimes as a digital print, before the tile is heated again. If they become chipped, this can sometimes result in the surface colour being removed and exposing the underneath layer. Porcelains are also tend to be made from clay but are much more dense and durable, with sharply formed faces. Most carry the colour and pattern throughout the entire thickness of the tile, making them more resistant to wear and chipping.