How else were tablets signed?

Other types of seals were also used. Stamp seals were small pieces of carved stone or metal which were stamped into the damp clay of a tablet.

Stamp seal with modern impression

Not everyone needed a seal, or could afford to have their own. These people would use their fingernail to 'sign' a tablet.

This is an example of a tablet which has been 'signed' with a person's fingernail mark.