Mineralogy of ceramic wares from the Augland workshop (c. 200–450 CE) in southernmost Norway: New insights from petrography, mineral chemistry and clay mineral X-ray diffraction

This pilot study of ten samples from the Early Iron Age ceramic workshop at Augland (c. 200–450 CE) in southernmost Norway identifies the microstructural and geochemical signatures of the main types of wares and relates these to the overall chronology of the site. Having the advantage of an already established chronology and related range of pastes, this study improves our understanding of key factors of the workshop’s technological development. A more detailed geological data set offers new insights into the dynamics between the initial main recipe, a remarkably stable feature throughout the workshop’s lifetime of more than 250 years, and later paste compositions, and into the provenance of imported tempering minerals. A novel mode of production entering Augland in the mid-4th century brought innovative ceramic paste recipes that were used alongside the traditional main recipe in the workshop’s final century. This pilot study adds important insights to the signatures of the two latest recipes during the first part of the 5th century. These recipes have been related to two successive technological pulses entering Augland, both of which were identified in a previous comprehensive statistical cluster analysis. However, our results reveal that these two recipes are both microstructurally and geochemically distinct, indicating the two technological pulses may have different geographical origins. By linking this new geological dataset to the established chronology of the Augland site, we present a framework for future provenance studies and regional database of ceramic material found at the Augland site.