Interesting that Nuremberg has been mentioned several times. It was there that the Krauswinckel family produced enormous amounts of Jettons or Tokens, known as 'Nuremberg Jettons'.
One maker was Egidius Krauswinkel (EK), who was active between 1570 and 1613.
The design dosen't match any of the normal designs, but perhaps this one was a 'special' for local use.