The Chalcolithic (Ancient Greek: χαλκός khalkos "copper" + Ancient Greek: λίθος lithos "stone") period 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.
An archaeological site in southeastern Europe (Serbia) contains the oldest securely dated evidence of copper making at high temperature, from 7,000 years ago. Copper smelting may have been invented in separate parts of Asia and Europe at that time or spread from an initial source by long-distance trade.
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