This panel in ivory was made in Cologne in about 1360-1380. It was used as the cover for a set of writing tablets depicting the martyrdom of St Thomas Becket of Canterbury. This is one of several ivories shwoing Becket's martyrdom, although it is the only one on which it is the sole subject depicted.
Ivory covers for writing tablets survive in good numbers from the fourteenth century. Wax writing tablets or panels of a hard material filled with layers of wax that could be inscribed with a stylus, were common in Antiquity and continued in use throughout the early Middle Ages. They were particularly useful for note taking, given their portability and the fact that their surfaces could be erased and reused.
The majority of such tablets would have been made of wood, although other materials such as gold, silver, bone and ivory were also used. In most cases the tablets formed part of a group of up to eight panels, only the covers of which were carved with imagery on their outer faces. The imagery on most surviving tablets and boxes derives primarily from diptychs, with a quality of carving lower than that commonly found on diptychs, at least partly as a result of the thinner ivory material on the tablets.