OSTRACON
A little ceramic pot sherd, as the one above, was called ostrakon in ancient Athens, meaning “shell” (English: ostracon, plural ostraca). They were used both for taking notes and for issuing tax receipts and legal documents. They also came in handy on the hill Pnyx, the centre of Athen’s democratic activities, when the citizens voted out misbehaving residents. The English verb “to ostracize” comes from this ancient piece of ceramic.