The Palatine Chapel at the National Palace of Sintra, used for Christian worship, is heavily marked by Mudejar influences in the decoration of its carved wooden ceiling, and also in its alicatado tiled floor. Until the second half of the 15th century, the alicatado tile (deriving from the Arabic al-liqât, which means pliers or nippers) was obtained through the piecing together of monochrome enamel tacelos (small ceramic fragments of various shapes and colours that had been glazed and cut beforehand). Creating this puzzle of geometrical knotwork motifs was a delicate, painstaking and expensive task.