Stone tools employed in prehistoric metal mining. A functional study of cobblestone tools from prehistoric metalliferous mines in England and Wales in relation to mining strategies by use-wear analysis and cobble morphometry

Abstract

This is a study of cobblestone tools from metalliferous mine sites in England and Wales dated to the Bronze Age which were most probably used to extract copper ore. The site assemblages studied are from the Great Orme, Copa Hill in Cwmystwyth, Nantyreira, Parys Mountain and Alderley Edge. The majority of the tools are hammerstones used to mine and beneficiate metal ore. Some of these have been modified to facilitate hafting. The functional uses of these tools have been identified by the form and position of use- wear on a macroscopic level. The recording procedure encompasses cobble morphology, the degree, type and direction of use, breakage patterns, the reuse of tools and tool fragments and the classification of hafting modification. The possibility of tool specialization within tool types has been examined by the analysis of use-wear and cobble shape and size. The analysis of stone hammer size suggests that the Great Orme material is related to specific working techniques employed to extract ore from the different types of ore deposits. Ore comminution has been demonstrated to have been generally achieved by ‘block-on-block’ crushing with flat-sided hammers. Conclusions are draw on the overall efficiency of ore extraction in the Bronze Age and theories on the organization of mining are presented. The sedimentary form of the cobblestone tools has also been examined, including the identification of natural abrasion marks and features. At Cwmystwyth and the Great Orme possible sources of cobblestones have been studied in order to assess the nature of cobble selection.