The relief is a terracotta (fired clay) plaque, large, thick, with the head of the figure projecting from the surface. To manufacture the relief, clay with small calcareous inclusions was mixed with chaff; visible folds and fissures suggest the material was quite stiff when being worked. The British Museum's Department of Scientific Research reports, "it would seem likely that the whole plaque was moulded" with subsequent modelling of some details and addition of others, such as the rod-and-ring symbols, the tresses of hair and the eyes of the owls. The relief was then burnished and polished, and further details were incised with a pointed tool. Firing burned out the chaff, leaving characteristic voids and the pitted surface we see now; Curtis and Collon believe the surface would have appeared smoothed by ochre paint in antiquity.