Clay Symbols (Calculi) (Replica)

Number symbols made out of clay

4000 B.C.

These seven differently shaped Clay Symbols, found in Uruk (southern Mesopotamia), are cast after originals in the possession of the German Archaeological Institute in Berlin.

These Calculi were used as memorial stones for certain quantities of certain trade goods.

Since abstract counting was still unknown, counting was always object-related, or rather an actual quantity was compared with these symbolic stones.

If a contract was concluded, the clay symbols were placed in a hollow clay ball.

A breach of contract meant that the clay ball had to be broken open again to inspect the objects inside.