text: Also during Phase II, copper and arsenical bronze production was practiced at the site.
  Norşuntepe provides first clear and unambiguous evidence of arsenical bronze production in this general area before the 4th millennium. It demonstrates that some form of arsenic alloying was being deliberately practised. Since the slag identified at Norşuntepe contains no arsenic, this means that arsenic-bearing materials were added separately. The evidence was discovered at the levels with Ubaid style ceramics, where also were found a number of structures related to the Mesopotamian architectural traditions. A related site in the area from the same time period is Değirmentepe, where arsenic-bronze was also produced around 4200 BC.
  The final Chalcolithic phases were characterized by small-scale single-room houses. Radiocarbon dating from the different Chalcolithic levels provided dates between 4300-3800 BC.