Cylinder Seals
Cylinder seals were first made in Mesopotamia, modern-day Iraq, soon after 3500 BC. Paper had not been invented, so documents were written in cuneiform (wedge-shaped characters made into wet clay to provide pictorial symbols for words and syllables) on clay tablets and then wrapped in clay envelopes. The seals were used to make an impression (or 'seal') in the soft clay, to indicate that the message on the tablet was genuine. In the same way, important documents are still sometimes 'sealed' by making an impression in bright red sealing wax. People continued to use cylinder seals to 'seal' ancient documents for about three thousand years.
http://www-oi.uchicago.edu/OI/UR/Seals.html
Treasures from theROYAL TOMBS of UR Cylinder Seals
Cylinder seals, references
Some Background on Gilgamesh
CYLINDER SEALS
Cylinder seals
Seals in Egypt
The Museum of Printing History
Some of the best preserved depictions of mythical events can be found on cylinder seals. They were tiny, amulet-like cylinders that were used in much the same way ring seals were used in Roman and later times. Since visual representation was believed to be a very powerful tool, the depictions alone of mythological events and mighty deities was believed to be enough to ward off evil demons or bring the wearer under the protection of his/her personal deity. They also served a more practical purpose: personal identity. Each individual family had their own seal, and individual family member, in turn, might have had different seals.
Cylinder Seals
