Porcelain is just one of the many varieties of ceramic tile. While the primary ingredient in porcelain is finely ground sand, porcelain tiles are composed of quartz, clay and feldspar. These ingredients are processed using very high pressure and are fired at a temperature ranging from 1200-1400-degrees Celsius. Due to its density and composition, unglazed porcelain tiles have many of the same excellent durability qualities as glazed ceramic tiles.