The composition is based on the central panel of the ' Baroncelli Polyptych' signed by Giotto. Both have as their subject the coronation of the Virgin Mary as Queen of Heaven, & intercessor for mankind. The surface of Daddi's painting, however, is more decorative than Giotto's, with a harmonious arrangement of gold-patterned pinks, whites & greys, dramatically contrasting with the bold celestial blue of Christ's robe. He also made the Virgin's pose deliberately ambiguous, so that we are unsure whether she is enthroned or kneeling in a posture of humility. This is the upper part of a panel that once had figures of four music-making angels & Saint John the Baptist & a deacon saint (probably Saint Stephen) in the lower part, which survives at Christ Church, Oxford. It is possible that this was a single independent panel, or that it was once part of a polyptych, made for the high altar of a church.