http://www.smith.edu/hsc/museum/ancient_inventions/images/hsc03a.jpg
3000 BCE
Seals were most often made of stone but also sometimes of bone, ivory, faience, glass, metal, wood, or even sun-dried or baked clay. A recessed inscription was carved onto the cylinder, which produced a raised impression when rolled on a clay tablet or envelope. Cylinder seals were used to protect vessels, clay envelopes and storeroom door latches from tampering. They guaranteed authenticity, marked ownership, indicated participation in a legal transaction and protected goods against theft.
http://www.britannica.com/blogs/wp-content/uploads/2009/07/iraq-art.jpg
Statue of Entemena
http://www.cbc.ca/arts/artdesign/story/2009/07/09/iraq-antiquities.html
A decorated nail from 2100 BC that would have been used to anchor a building's foundations to the ground is shown Thursday in the Netherlands. (Dutch Education, Culture and Science Ministry/Associated Press)