CHALCOLITHIC

   An archaeological period (literally “copper-stone” age) that refers to increased use of metallurgy, especially of copper, toward the end of the Neolithic period. In Mesopotamia, the Chalcolithic period lasted approximately from the sixth to the fifth millennia B.C. Pilot sites are Tepe Gawra and Tell Arpachiya in the north, and Eridu and Tell Awayli in the south. For southern sites, the term Ubaid period is also used, and for the north, Halaf period. In this phase, all the achievements of the preceding period were further developed; horticulture and agriculture spread, and more and more people adopted a sedentary lifestyle. The archaeological evidence points to increased settlement size, increased specialization and professionalization, and higher labor inputs. All ecological niches and their wild resources (fish, water fowl, game, wild legumes) were exploited, and new cultigens were planted in fields and gardens, making use of hydro-technological inventions such as field irrigation.

   The Chalcolithic period also saw the introduction of fundamentally new technologies. Particularly striking is the hand-painted, sometimes glazed potteryshowing an unparalleled degree of perfection. Pottery sets, found in many graves, were probably used in rituals and banquets where status could be displayed (see CRAFTS; FUNERARY AND BURIAL PRACTICES). Metallurgy was less developed in Mesopotamia than in neighboring countries such as Iran. Gold was introduced, and arsenic bronze appeared in the upper Euphrates region in the Ubaid period. There is some evidence from Tell Awayli of a weaving loom (see TEXTILES).

   Stone was also worked with more sophistication; it was now possible to work stones with a hardness of 4 to 7 on the Moh’s hardness scale. The presence of exotic stones, such as lapis-lazuli from Badakhshan or turquoise from Central Asia, points to an interlinking supply system. Exchange of goods seems to have been an important factor of Chalcolithic socioeconomics, as was the practice of seals and sealing documents. Some scholars propose that Chalcolithic communities were on the way to forming states (“incipient statehood”), given the whole-scale application of traditional inventions, efforts at maximizing energy output, and increasing full-time sedentarization.