1) Aeneolithic 2) Eneolithic 1) Aeneolithic 
The Chalcolithic (k; χαλκός khalkós, `copper` and λίθος líthos, `stone`) period or Copper Age, also known as the Eneolithic/Æneolithic (from Latin aeneus `of bronze`), is a phase of the Bronze Age before it was discovered that adding tin to copper formed the harder bronze. The Copper Age was originally defined as a transition b...
chalcolithic Belonging or relating to the transitional period between the Neolithic and Bronze ages, beginning around 400 B.C., when the use of copper became more prevalent.
of, pertaining to, or characteristic of the Copper Age; Aeneolithic.