Ostrakas were ballots made from pottery.  On them an Athenian citizen inscribed the name of another citizen who he would like to see banished from Athens.  The practice of holding regular banishment proceedings ended around 415 B.C., during the life of Socrates.

The above image is republished with permission of the Hellenic Ministry of Culture.  The Ministry's Website, Odysseus, has the following address: http://www.culture.gr/

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