This paper presents geochemical data from a blanket peat located close to a Bronze Age copper mine on the northern slopes of the Ystwyth valley, Ceredigion, mid-Wales, UK. The research objective was to explore the possibility that the peat contained a geochemical record of the pollution generateD by mining activity. Four peat monoliths were extracted from the blanket peat to reconstruct the pollution history of the prehistoric mine. Three different geochemical measurement techniques were employed and four copper profiles have been reconstructed, two of which are radiocarbon-dated. The radiocarbon dates at one profile located close to the mine confirm that copper enrichment occurs in the peat during the known period of prehistoric mining. Similar enrichment of copper concentrations is shown in one adjacent profile and a profile within 30 m away. In contrast, copper was not enriched in the other radiocarbon-dated monolith, collected approximately 1.35 km to the north of the mine. Whilst other possible explanations to explain the copper concentrations are discussed, it is argued that the high copper concentrations represent evidence of localised atmospheric pollution caused by Bronze Age copper mining in the British Isles. The results of this study suggest that copper may be immobile in blanket peat and such deposits can usefully be used to reconstruct atmospheric pollution histories in former copper mining areas.

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This paper presents records of the atmospheric deposition of lead and zinc close to a former metal mining area as recorded by an upland blanket peat that has accumulated on the northern slopes of the Ystwyth valley, Dyfed, mid-Wales, UK. The research objective was to explore the possibility that the peat contained a geochemical record of the pollution generated by mining activity during the last four millennia. Four monoliths were extracted from the blanket peat to reconstruct the pollution history of lead and zinc mining. Three different geochemical measurement techniques were employed, and five lead and zinc profiles have been reconstructed, two of which are radiocarbon-dated. In the radiocarbon-dated monoliths lead enrichment occurs in the peat during the Roman occupation whilst both lead and zinc concentrations increase from the Mediaeval period until the early part of the 20th century. Similar enrichment of lead and zinc is shown in the remaining profiles. Whilst other possible explanations are discussed, it is argued that the high lead concentrations represent evidence of atmospheric pollution caused by mining. Zinc, however, may have suffered from post-depositional mobility. The results of this suggest that lead is largely rendered immobile in blanket peat and can be used to reconstruct atmospheric pollution histories in former lead mining areas.

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