Piero Della Francesca’s Brera Madonna, detail of the niche. Executed in Pinacoteca di Brera of Milan. / The shell was a symbol of the new Venus, Mary and the egg is generally considered a symbol of the Creation.
Piero della Francesca (c. 1415 – October was a painter of the Early Renaissance. As testified by Giorgio Vasari in his Lives of the Artists, to contemporaries he was also known as a mathematician and geometer: Madonna del parto