Byzantine bronze bread stamp

During the Roman Imperial period, bakeries were legally required to stamp their bread with a unique seal to trace the source and prevent theft of military rations.

In the Byzantine Empire, bread stamps evolved and were used by private individuals, as a sign of ownership, for religious purposes and for organising. They appear in a great variety of shapes, inscriptions and symbols. The common characteristic of Byzantine bread stamps was the emphasis in drawing fracture lines that indicated to the priest where to cut the loaf. These lines become even more important on Eucharistic stamps that marked the consecrated bread for communion.

In the Roman and Byzantine Empire ovens were used by multiple people at the same time. Stamping the dough before baking helped to identify the owner of the finished bread.

Square-shaped bread stamps are more rare than their circular counterparts because the loaves themselves were round. A square shape pressed into a round loaf tends to distort the roundness of the loaf. Square loaves were not feasible, since the corners would brown and harden before the rest of the loaf, not to mention the difficulty in keeping the loaf square once the yeast begins taking effect. Thus, this stamp would have once been pressed into a round loaf. As the loaf baked in the oven, the stamped image would grow larger as the loaf expanded. After the bread was finished baking and cooled, the loaf would be cut into pieces, leaving the stamped piece intact.