Its pulpit is decorated with the richest polychrome mosaic that can be found anywhere in Sicily or south Italy, and is quite Moslem in its brilliance.
He stands as a leader in the practice of polychrome, since widely diffused, and by his writings and example did much to reinstate the ancient union between architecture, sculpture and painting.
Adjoining it to the north is the Cappella Colleoni, with a richly sculptured polychrome façade, and a modernized interior, containing the fine tombs of Bartolommeo Colleoni (c. 1400-1475), a native of Bergamo, and his daughter Medea.
The doorway of one room (now in Berlin Museum) was decorated with polychrome glazed tiles with the name of King Neterkhet.
The most magnificent part of the exterior and indeed the finest polychrome monument in existence is the west façade, built of richlysculptured marble from the designs of Lorenzo Maitani of Siena, and divided into three gables with intervening pinnacles, closely resembling the front of Siena cathedral, of which it is a reproduction, with some improvements.