I must confess a certain ignorance when it comes to medieval metalwork and enamels. But here is a pretty thing.
This is Châsse or casket from Limoges, c. 1190-1200. A Châsse was a reliquary shaped sort of like a house with a sloping roof and triangular gabled ends. Limoges was center enamel work at the time. This is Champlevé enamel. Champlevé is created by casting a metal piece with impressions for the area to be enameled. The depressions are then filled with powdered glass. The entire piece is the fired and the glass melts and fuses with the metal.
This is reliquary for St. Thomas Becket. The main body shows his murder while the roof shows his entombment. On the end is a saint, probably Becket himself.
The reliquary is in the Musée de Cluny in Paris.