The Gold Mine
Welsh gold has been mined since at least the Bronze Age, and the purity of the gold has added an extra reason for its extraction.  The Romans certainly valued it above other sources of gold perhaps because it often has a reddish tint in comparison to gold extracted elsewhere. This is due to the fact that the gold is stained by copper which lies in the rock next to the veins of gold.
Although there is no evidence for gold mining taking place at Coed-y-Brenin in the time of Rhiannon and Geraint there are certainly rich veins of gold here, and gold would have been visible in the rivers and streams.

The Gwynfynydd Gold Mine closed in the late 1990s although there are often rumours about it reopening due to the increase in the value of gold.  The last gold mine to operate was the Dolaucothi Gold Mines near Pumpsaint which is also a listed ancient monument and now in the care of the National Trust and billed as a quirky visitor attraction