Rotary motion in Iron Age gold work: Annular ornaments and their decoration

International audienceRotary motion tools are key in the development of complex technologies in gold working since the Late Bronze Age in Western Europe. This paper deals with specialised Early Iron Age metal working tools and techniques, more precisely with the production of annular sheet ornaments using rotary motion, attesting for the first time the goldsmith’s technical knowledge to make use of a spinning lathe in order to create a specific ornament shape with an economic use of precious metal. Annular sheet ornaments such as neck and arm rings form two important groups of gold jewellery during the West Hallstatt period in Southwest Germany, Eastern France and Switzerland. This study explores their particular manufacturing techniques for shaping and decoration by tool mark analyses and experimental archaeology. The technological aspects of these sheet ornaments reveal on the one hand the use of rotary motion instruments for the shaping of the complex relief, and on the other hand a specific way of chasing and punching for their ornamentation