Mosaic is my favorite visual art form. I’m not sure why, but I think it has to do with its colour and abstraction. It’s durability is also admirable. I have so many favorites, and this is one of them. It’s a detail of the face of Mary in the Deisis mosaic (a depiction of the triad of Mary, Jesus, and John the Baptist) in the upper western gallery of Hagia Sophia in Istanbul. It dates from around 1200, over 5 centuries after that famous church’s construction. Mary bows her head towards Christ, in worship but also with sad eyes because her son has been taken from her and sacrificed for humanity’s sins. She wears over her head the purple Maphorion, edged in gold; an indication of her imperial nature. Underneath that we see the edge of her blue robe, indicative of her role as Queen of Heaven (imperial purple; royal blue). On the brow of her Maphorion is a golden star, an ancient symbol that predates Christianity and was associated with the fertility goddess cults of antiquity. Her eyes appear on the verge of producing tears, while her lips seem to quiver with the pain of Christ’s crucifixion. But as she sees him in the Deisis he is in splendour, victorious over death: the Pantocrator, ruler of all and judge of the universe. By 1200 Byzantine mosaic artists had begun  imitating the subtleties of painting in their art, trying to reproduce shading and gradations of colour and shadow, articulating the careful play of light over a cheek or swath of waving drapery. Here, we have a good example of these experiments with the medium.