In addition to the roundels with Saint Bonaventure and Saint Louis, the Basilica  dell’Osservanza is house to another two marvellous masterpieces by Andrea della Robbia (1435 – 1525). He came from a  famous family of sculptures, specialised in the manufacture of glazed polychrome terracotta creations, a technique invented around 1440 by Luca della Robbia. This process, which entails the layering of glass enamel on the terracotta surface, confers the works a high resistance to atmospheric agents and bright colours, enhancing the plasticity of the milky white figures against the light blue background. An excellent example is given by the retrotabula representing the Coronation of the Blessed Virgin and Saints in the second chapel on the left; dating back to the 1480s, even this work of art was shattered by bombings during World War 2, just like the roundels, and was restored after a painstaking repair. The central part portrays, facing each other, Jesus Christ and the Blessed Virgin, who bows her head in receiving the crown from her Son: In this way Mary, the humble maid, is part of her Son’s Glory and elevated above the angels, where she reigns in glory and intercedes for all humanity. The Holy Spirit in the form of a dove is between them, while cherubs and beautiful angels playing trumpets in sign of joy surround them. Below, some saints watch the event: on the left . . .