The discovery of evidence to suggest that copper ore was exploited at the Great Orme on a considerable scale in prehistory is of great significance in our understanding of the development of metalworking technology in the British Isles.In the past, the apparent absence from the archaeological record of a contemporaneous native mineral source for the production of copper and copper alloy artefacts during the Bronze Age has led to the assumption that raw materials, as well as metal technology, were imported from abroad. Alternatively, whilst accepting that local resources could have been exploited, it was assumed that these would have been obliterated by the mining operations of later centuries.There are now several sites on the British mainland and in Ireland which have been identified and dated as having been exploited for copper ores during the Bronze Age, of which a number, as on the Great Orme, had since seen intensive working during the 18th and 19th centuries AD. AS yet, much of the evidence has come essentially from surface excavations, but at the Great Orme surface excavation combined with underground exploration has revealed a system of workings of truly remarkable size. A series of 10 radiocarbon dates has been obtained from within the mine complex, indicating that working was carried out for over a thousand years spanning the Early to Late Bronze Age.The true extent of the surviving prehistoric workings is yet to be realized but present evidence indicates mining activity covering an area in excess of 24,000 square metres, incorporating passages totalling upwards of 5 km, penetrating to a vertical depth of 70 m.Much of the archaeological evidence contained within this report has been gained from detailed excavation carried out within surface workings, which in their own right constitute a sizeable part of the prehistoric mine. From the surface area presently exposed it is conservatively estimated that 40,000 cubic metres of material was removed during the Bronze Age. Much of the early technology represented within the surface workings reflects the technology employed in the deep workings, with the additional evidence of ancillary operations which would seem to relate solely to surface locations.Whilst the excavations reported in this paper relate to surface, or near surface, workings, they must be seen in the context of a labyrinthine complex of prehistoric workings recorded at depths of over yom (Jenkins & Lewis 1991; Lewis 1994). These deep workings are the subject of parallel studies to be reported elsewhere. The known underground and surface prehistoric workings are on a scale so far unparallelled in Britain and are of international significance. Elsewhere in Europe there is evidence for the mining of copper ores at Ai Bunar in Bulgaria dated to 5840 BC (Cernych 1978) and at Rudna Glava in former Yugoslavia dated to 4715 BC (Jovanovic 1979). Evidence for subsequent copper mining has been dated to 3785 BC in southern Spain (Rio Tinto area: Rothenburg & Blanco Freijeiro 1980) and to 3330 BC in Austria (Mitterberg; Pittioni 1951), marking an apparent development and extension westwards and northwards of copper technology. More recently, the dating of two sites in the south of France to around 3330 BC, at Cabrieres (Ambert et al. 1990) and Bouche Payrol, near Brusque (Barge 1985), has confirmed another area of Bronze Age working.
Ageing of low-firing prehistoric ceramics in hydrothermal conditions
