Chalcolithic. Wikipedia: or Copper Age, also known as the Eneolithic/Æneolithic (from Latin aeneus "of bronze"), is a phase of the Bronze Age in which the addition of tin to copper to form bronze during smelting remained yet unknown by the metallurgists of the times. The Copper Age was originally defined as a transition between the Neolithic and the Bronze Age. The literature of European archaeology, in general, avoids the use of 'chalcolithic' (the term 'Copper Age' is preferred), whereas Middle Eastern archaeologists regularly use it. The Copper Age in the Middle East and the Caucasus began in the late 5th millennium BC and lasted for about a millennium before it gave rise to the Early Bronze Age. The transition from the European Copper Age to Bronze Age Europe occurs about the same time, between the late 5th and the late 3rd millennia BC.