a series of plates depicting the mosaics in 1695 for Louis, Duke of Burgundy. The mosaic panels are surrounded by richly gilded stucco decoration. The blue background creates an optical illusion giving the impression of an architectural framework opening to the sky above the chapel. The panels look like illusionistic skylights between the gilt stucco ribs while God is standing on the edge of the central oculus. The traditional interpretation of the dome is that the composition shows the Creation of the World. Another interpretation, proposed by John Shearman, claims that it represents the cosmos as described by Plato in a Christianized Neoplatonist form. This idea had a widespread popularity in the Renaissance. In this case the dome is a depiction of the "Realm of the Soul after Death" with God, the Father receiving the soul (of Agostino Chigi) in his new home. The presence of the signs of the zodiac corroborates this interpretation because the signs were symbols of the passage of time in eternity, and they appeared in antique funeral art around the image of the departed. Tambour and spandrels Raphael intended mosaics for the decoration of the tambour and the spandrels but these were never executed. In 1520 Francesca Ordeasca commissioned Luigi da Pace to carry out this task in no more than four years. In 1530 the executors of Agostino Chigi's will commissioned Sebastiano del Piombo to produce eight oil murals between the windows and four tondi on the spandrels. As Sebastiano was working leisurely on the large altar-piece, he made only preparatory drawings. Two studies in the Louvre show God the Father creating the Sun and the Moon and separating Light from Darkness. Another drawing in the Royal Library in Windsor shows God with arms outstretched, a gesture associated with creation. The drawings were obviously inspired by Michelangelo. Around 1548-50 the Chigis commissioned Francesco de' Rossi (or Il Salviati) with the same task. Supposedly de' Rossi was recommended by his patron, Cardinal Giovanni Salviati (whose surname he adopted) because the cardinal was linked to the Chigi family through the 1530 marriage of his relative, Giuliano with Camilla Chigi, the daughter of Agostino. The four tondi of the spandrels depict allegoric representations of the Seasons. In 1653 they were restored by Antonio della Cornia by order of Fabio Chigi. The murals were described as being seriously damaged in 1842. The iconography of the paintings is classical.