The Chalcolithic or Copper Age is the transitional period between the Neolithic and the Bronze Age.[1]
It is taken to begin around the mid-5th millennium BC, and ends with the beginning of the Bronze Age proper, in the late 4th to 3rd millennium BC, depending on the region.
The development of states—large-scale, populous, politically centralized, and socially stratified polities/societies governed by powerful rulers—marks one of the major milestones in the evolution of human societies. Archaeologists often distinguish between primary (or pristine) states and secondary states. Primary states evolved independently through largely internal developmental processes rather than through the influence of any other pre-existing state.
The earliest known primary states appeared in Anatolia c. 5200 BC,[2] in Mesopotamia c. 3700 BC,[citation needed], in Greece c. 3500 BC,[3] in Egypt c. 3300 BC,[citation needed]
in the Indus Valley c. 3300 BC,[citation needed]
and in China c. 1600 BC.[citation needed]
In Africa, discoveries in the Agadez Region of Niger evidence signs of copper metallurgy as early as 2000BC. This date pre-dates the use of iron by a thousand years.Copper metallurgy seems to have been an indigenous invention in this area, because there is no clear evidence of influences from Northern Africa, and the Saharan wet phase was coming to an end, hindering human interactions across the Saharan region. It appeared to not be fully developed copper metallurgy, which suggests it was not from external origins.
^The New Oxford Dictionary of English (1998) ISBN0-19-861263-X, p. 301: "Chalcolithic /,kælkəl'lɪθɪk/ adjectiveArchaeology of, relating to, or denoting a period in the 4th and 3rd millennium BCE, chiefly in the Near East and SE Europe, during which some weapons and tools were made of copper. This period was still largely Neolithic in character. Also called Eneolithic... Also called Copper Age - Origin early 20th cent.: from Greek khalkos 'copper' + lithos 'stone' + -ic".
