Piero della Franchesca, Brera Altarpiece, 1472

Painted by Piero della Franchesca for Lord Frederico da Montefeltro, a dedicated patron of Italian artists, the Brera Altarpiece shows an assembled half-circle of various saints and angels gathered around the Madonna and Child. In the foreground, an armored Montefeltro is kneeling before Jesus. Because of a dueling accident, Montefeltro had a scar across the right side of his face, and part of the bridge of his nose was missing - meaning he had to be portrayed in profile, from his good side.

Although the faces and proportions of the assembled saints may be questionable, and baby Jesus looks about to roll off Mary's lap, above them stands a strikingly gorgeous barreled arch in perspective, a seashell-like dome, and an egg dangling from its tip, a symbol of the creation. Various theories about this enigmatic symbol link the seashell to depictions of Venus or to a symbol of the immaculate conception (since oysters create pearls without male intervention). The egg may also represent a hope of regeneration or simply be a reference to the ostrich in the Montefeltro crest. This painting is not unique in showing an egg hanging from the ceiling, and indeed real ostrich eggs were sometimes hung in churches as curiosities and reminders of God's grace.

When rediscovered in the 19th century, the paint had darkened almost out of recognition; modern reconstruction allowed the intricate details of the clothing, the reflections on Montefeltro's armor, and the Oriental rug beneath Mary's throne to return to focus. The painting, some scholars suggest, was commissioned to celebrate the birth of Montefeltro's son Guidobaldo. Whatever its original purpose or the true symbolism of the enigmatic egg might be, this altarpiece holds layers of symbolism and intricate details not obvious on a first viewing.