Small stone cylinder engraved in intaglio on its surface to leave impressions when rolled on wet clay. It first appeared c. 3400–2900 BC and is considered to be one of the finest artistic achievements of Mesopotamia. The earliest examples used geometric or animal patterns; later seals incorporated the owner's name and depicted a variety of motifs. They were used to mark personal property and make documents legally binding. The seals were adopted in Egypt and the Indus civilization.