Photograph of the enamelled cover of the Maastricht case, created in the early eleventh century and now in the collection of the Louvre, Paris (MR 349). The central, rectangular panel depicts the Crucifixion that takes place under an archway. Christ's figure is flanked by the Virgin on the left and St John on the right. Two busts of the personifications of the moon and sun are visible by the cross's top.

The piece is set in a wide frame, the sides of which are mainly decorated with bezel-mounted cabochons. The frame's four corners are occupied by the symbols of the apostles, all enclosed in squares and accompanied by the apostles' names engraved in Latin. St John's eagle (top left) and St Mark's lion (bottom right) are rendered in cloisonné enamel, whereas St Luke's bull (bottom left) and St Matthew's angel (top right) in champlevé enamel.