text: The smelting of gold began sometime around 6000 – 3000 BC. According to one source the technique began to be in use in Mesopotamia or Syria. In ancient Greece, Heraclitus wrote on the subject.
  According to de Lecerda and Salomons (1997) mercury was first in use for extraction at about 1000 BC, according to Meech and others (1998), mercury was used in obtaining gold until the latter period of the first millennia.
  A technique known to Pliny the Elder was extraction by way of crushing, washing, and then applying heat, with the resultant material powdered.