The Kerameikos was the potters' quarter of Athens. It contained a variety of small workshops, and probably a few larger ones. In 1852, during building activity in Ermou Street, the workshop of the Jena Painter was discovered. The artefacts from it are now on display in the University collection of the Friedrich Schiller University of Jena. According to modern research, the workshops were owned by the potters. The names of about 40 Attic vase painters are known, from vase inscriptions, usually accompanied by the words (égrapsen, has painted). In contrast, the signature of the potter, (epoíesen, has made) has survived on more than twice as many, namely about 100, pots (both numbers refer to the totality of Attic figural vase painting). Although signatures had been known since c. 580 BC (first known signature by the potter Sophilos), their use increased to an apex around the Pioneering Phase. A changing, apparently increasingly negative, attitude to artisans led to a reduction of signatures, starting during the Classical period at the latest. Overall, signatures are quite rare. The fact that they are mostly found on especially good pieces indicates that they expressed the pride of potter and/or painter.