A Bronze Age copper mine in North Wales is likely to have been the site of Britain’s first mining boom, with a ‘golden age’ of production between c.1600 and 1400 BC seeing its copper travel as far as Brittany and the Baltic, new research suggests.
The Great Orme is one of Europe’s largest copper mines, but it was previously thought that its size was the result of small-scale seasonal extraction over nearly 1,000 years by farmers working part-time. However, new research recently published in Antiquity suggests that there was a period of large-scale production during which the mine supplied the whole of Britain, with some trade or exchange into Europe, which would have required a mostly full-time mining community.
Past analysis had concluded that the Great Orme mine was not an important, large-scale producer of copper in the Bronze Age because it could only produce a metal low in impurities, which was uncommon in the metalwork of that period. However, an extensive new study by the University of Liverpool, with support from the Université de Rennes, which combines archaeological and geological expertise with the latest analytical techniques, has revealed that the mine produced a distinctive metal rich in nickel and arsenic. This discovery radically changes the metal-supply picture of the Middle Bronze Age, with the mine making Britain self-sufficient in copper for about 200 years, and trading metal with Europe.
Samples of copper ores were taken through several kilometres of the Great Orme Bronze Age workings, and a chemical and isotopic ‘fingerprint’ was defined. Confidence in the ‘fingerprint’ was increased as it matched fragments of bronze recovered from metal tools found in the mine, as well as copper metal fragments from the Bronze Age smelting site at Pentrwyn, 1.2km away. The next stage of the analysis was to compare the databases of British and European Bronze Age metal artefacts and to find those consistent with material from the Great Orme, in order to highlight the main period of activity and its geographical distribution. Using this method, scientists were able to see that metal from the mine dominated Britain’s supply for up to 200 years (c.1600-1400 BC), with some metal being traded in the form of palstave axes into continental Europe, stretching across northern France, the Netherlands, and as far as Sweden.
This extraordinary 200-year copper boom of high production at the Great Orme mine suggests that Britain was much more integrated into European Bronze Age trade and exchange networks than had previously been thought, given that Britain was a region of scattered farming communities. After the boom, the metal is rarely seen in metalwork analyses, but radiocarbon dating shows that small-scale workings continued at the Great Orme in a twilight period lasting another five centuries. This change probably correlates with the exhaustion of the richly mineralised central area of the mine, now a large underground cavern and a surface pit, leaving the narrow veins that required maximum effort for minimal output.
Text by Dr R A Williams