 The opaque pottery lamps would have been completely useless for lighting and they instead served a symbolic and decorative function.The lamps from Bayezid II's mausoleum are decorated with bands of geometric motifs and "kufic" inscriptions but around the centre they have a very prominent broad band containing large rosettes and stylized lotus blossoms.After the conquest of Constantinople in 1453, the Ottoman sultans started a huge building programme.