Analytical investigation of 14th century stained glass windows from Santa Croce Basilica, Florence. Glass types and weathering phenomena

The Basilica di Santa Croce (Basilica of the Holy Cross) is the major Franciscan church in Florence (Italy) and the largest Franciscan church in the world. The construction began in 1294 and the church was consecrated in 1442. Since the beginning the Basilica became one of the most important religious centers and the most prominent families in Florence had their chapel in the church sumptuously decorated with frescoes and glass stained windows painted by the masters of that time. In the church there are 22 stained glass windows. During the last ten years the Opera di Santa Croce started a restoration campaign of some of the stained glass windows. In this paper the archaeometric data collected from six of the most important stained glass windows are compared. According to stylistic studies the six windows belong to a period spanning from the first/second decade to the end of the fourteenth century.