The Madonna del Cardellino

Raphael painted this around 1506 as a wedding present for a friend, the Florentine wool merchant Lorenzo Nasi. In it the young John the Baptist holds out a goldfinch, and the Christ child reaches to stroke its head. The bird was a familiar emblem of the Passion, said to have got the red patch on its face from Christ's blood, so a tender family scene quietly carries the shadow of what is to come. The painting nearly did not survive. In 1548 the Nasi house on a Florentine hillside collapsed in a landslide, and the panel broke into 17 pieces. Someone pinned it back together with nails and painted over the cracks, and it stayed that way for centuries. Between 1999 and 2008 restorers took a full decade to undo that repair, using X-rays and microscopes to find every old fracture before stabilising it. The 17 breaks are still traceable underneath, mapped across a picture that looks, from a step back, entirely whole.