Silver Altar (Saint John's Treasure)

Back to the 1300s the guild in charge of the preservation of the Baptistery was the so called Calimala Guild. In the 1360s the Guild decided to replace the existing 13th-century silver altar with a new, more precious one.

The Treasure was commissioned in 1366; the task of building it would have been assigned to the winner of a competition. However, the various reliefs happened to be assigned to a range of participants. Famous sculptors and goldsmiths such as Leonardo di ser Giovanni, Michele di Monte, Tommaso Ghiberti, Matteo di Giovanni, Bernardo Cennini, Antonio del Pollaiolo and Andrea del Verrocchio were challenged in the creation of the masterpiece. The Treasure required more than a 100 years of work, as well as more than 400 kg of silver and 1050 enamelled plates. The result of such an effort is an extraordinary synthesis of the main trends of the Florentine goldsmithing and sculpture that flourished between the Gothic and the Renaissance.

The Treasure decorated the front side of the High Altar in the Duomo until the end of the 14th century when it was moved to the altar in the centre of the Baptistery. In 1441 the central niche was realised in order to host the statue of the Baptist, a work by Michelozzo di Bartolomeo. In 1477 the decision to turn the Treasure into an independent altar was taken.

The frequent assemblies and reshuffles which took place during the centuries have altered the original order of the reliefs and some parts have been damaged or even lost. The very first great restoration was achieved by the Opificio delle Pietre Dure in 2012, after 6 years of works. During those years the masterpiece was disassembled into more than 1500 pieces and underwent a meticulous cleaning.

Today, this unique goldsmithing example is preserved in the Treasury Room of the Museo dell’Opera del Duomo, inside a showcase that keeps the object under nitrogen, assuring the ideal humidity and temperature.