In the attic, the decorative motif of the octagonal stars recurs. As they are formed by the interweaving of two squares, the stars symbolise the union between heaven and earth. Octagonal stars, flat and carved, circumscribe an eight-petalled flower. This theme, which later spread to Sicily and is also present in the Palatine Chapel, could originally be seen as a decorative element in a 10th century Fatimid-style ceiling in Cairo.
