Encaustic or inlaid tiles are ceramic tiles in which the pattern or figure on the surface is not a product of the glaze but of different colors of clay. They are usually of two colours but a tile may be composed of as many as six. The pattern appears inlaid into the body of the tile, so that the design remains as the tile is worn down. Encaustic tiles may be glazed or unglazed and the inlay may be as shallow as 1⁄8 inch (3 mm), as is often the case with "printed" encaustic tile from the later medieval period, or as deep as 1⁄4 in (6.4 mm).