Stone Tools from Prehistoric Mining Sites in North Tyrol, Austria: Typology – Terminology – Material Properties

Abstract

Mining archaeological field prospections and excavations conducted by the Research Center HiMAT at the University of Innsbruck yielded proof of extensive copper ore mining from the late Middle Bronze Age to the Early Iron Age (1300 - 700 BC) in the mining regions of Kitzbühel-Jochberg and Schwaz-Brixlegg in Northern Tyrol. This paper deals with stone tools collected at prehistoric mining sites and focusses on their typology, material properties and the problem of terminology. Petrographic analyses show a conscious selection of special stone materials for different applications. Typically, hard and tough metamorphic rocks collected from river gravel banks or glacial deposits of alpine valleys were used as raw materials for tool production. In general, well-rounded pebbles and boulders of amphibolite, garnet-amphibolite and eclogite were the preferred rock type used for percussion tools. According to the archaeological evidence, such stone tools were mostly used in the ore beneficiation process (crushing, to some extend also grinding) and have only rarely been found in connection with underground mining activities. For further beneficiation processes (grinding), other properties of the stone material such as abrasive capacity were required. In this context, boulders of orthogneiss/gneiss were the favoured rock material for netherstones (anvil stones and lower grindstones) and upper grindstones. The investigation of hafting modifications visible on stone tools shows that several hafting methods can be discussed, and that cords from plant fibres as well as straps of animal skin/leather could have been used for this purpose. Analysis of traces of wear provide information on the former function of the stone tools as well as on their practical application.