Gold at Dolaucothi
Discover more about the history of gold at Dolaucothi over the centuries.
In the world of geology, the presence of gold at Dolaucothi is a complete anomaly. In geological terms, there shouldn’t be gold here, which makes this place even more unique.
It’s one of two areas where gold has been found in Wales, the other being the Dolgellau gold belt in Gwynedd.
Dolaucothi is the only known mine to have been exploited in Roman times in the UK.
How did the gold form?
To understand how it formed here we need to look at the geology of the area. The bedrock in this area is approx. 438Ma, in geological terms, lying close to the Ordovician-Silurian contact. It’s comprised mostly of Silurian shales which forms initially in a marine environment. If you look closely at the mine walls, you can spot signs of this marine environment by finding sea floor ripples.
During a mountain building event, the Caledonide Orogeny, the rocks fold, shear and thrust under the enormous pressures built up in the crust.
Dolaucothi is located on a major fold for this area, the Cothi Anticline. The gold itself is found in the apex of the folds and in the quartz veins that formed either as thin discontinuous veins or lenses, the richest ores contain an abundance of pyrite (fool’s gold).
The mined zone is around 1.1km in area, marked on the surface by numerous shallow pits, trenches, adits and shafts.
The most lucrative deposit, known as the ‘Roman Lode’, a saddle reef deposit, which was mined during the last period of mining between 1935 and 1938.
What happened to all the gold mined at Dolaucothi?
For a mine dating back to Roman times, over the years a vast amount of gold would have been extracted from Dolaucothi – but where did it all go?
We know very little about what happened to the gold after it left Dolaucothi. Significant nearby finds suggest that it led to the creation of very beautiful decorative gold items.
On a nearby field back in 1797 a farmer ploughing his field made an exciting discovery. A cache of gold decorative items were found, including a fragment of a Roman gold serpent-headed bracelet, now in the British Museum.
These items are part of the British Museum Collection and you can even have a look at them online on the British Museum website.
There’s also the Royal family link to Welsh Gold, most of their collection is from the Dolgellau mines, but we’re told that some of it can be linked to Dolaucothi.
The family that lived and mined at Dolaucothi in the 17th century, the Johnes family, are known to have commissioned some jewellery from the gold found at the mines, sadly we can no longer trace the location of that collection. How exciting would it be to re-discover this one day!