An Impressed Pottery Sherd: A Chalcolithic Newfound in the Southern Highland of Abharroud River Basin

In prehistoric studies of iran, the abharrood river basin, located on the east of zanjan province and in the northwest border of the central plateau, is one of the little-known and dark regions. studying this region according to its environmental features and geographical location is important for understanding regional relations and interregional interactions between three cultural-geographical areas, the northwest, the west and the central plateau. so far, this region has not undergone major archaeological research and our knowledge of the nature of the prehistoric settlements is imperfect. a new trend in regional archaeological research began with two seasons of surveys, in 2003 and 2005. these surveys shed a light on the past of this region. in the first season, the site of chakhmaqlokh, in the southern highlands of the abharrood river basin, was identified. in 2009, on a second visit, cultural material of the chalcolithic period and a pottery sherd with a flat seal impression were collected from the surface of the site. it is likely that this sherd is the oldest piece of pottery with a seal impression that has been ever found in iran. therefore, valuable knowledge about important aspects of chalcolithic settlements in this region can be determined. after describing the area and introducing the site, the authors study the surface material and introduce, compare and date the sherd.