The Annals of the Four Masters (a chronicle of medieval Irish history created by monks created in 1632) which refer to the discovery of gold in Ireland in 1600 BC approx. and further state that the gold was smelted in the forests south of the present-day capital of Ireland, Dublin. 

While there is no evidence of historic mining in Ireland, there is now a greater likelihood that the prehistoric ornaments were made from Irish gold.  The way people would have found gold was by searching through the deposits left by rivers and streams.  One such river where this was known to take place was the Gold Mines River, Co. Wicklow.