Portable X-ray fluorescence analysis (P-ED-XRF) of sourcing and production series of the iron age ceramics from Basel-Gasfabrik (CH)

Basel-Gasfabrik is a Late Iron Age settlement (2nd/1st century BC) on the banks of the river Rhine. A large part of the 15 ha
settlement was excavated over several decades, resulting in an extensive body of ceramics. As part of the research project
“Über den Grubenrand geschaut” (Thinking outside the pits) some of these ceramics were analyzed using both portable X-Ray
Fluorescence Analysis (p-ED-XRF) as well as typological methods.
In addition to tackling methodological questions concerning sample preparation, precision of the instrument and possible con-
tamination through soil bedding, the main focus is the geochemical characterization of the settlement ceramics of Basel-Gas-
fabrik. Combining the geochemical results with already available micromorphological data and previously prepared macroscopic
sample descriptions (grouping) ensures a substantiated interdisciplinary approach. Whereas for the wheel-thrown fine ceram-
ics, the focus lies on the differentiation of local production series, of main interest for the coarse pottery is the provenance of
typologically striking vessels. Some of them show macroscopically discernable tempering with muscovite and crushed fossils,
that don’t occur naturally in the area surrounding the settlement.
Contrary to expectations, it appears that in the late Iron Age handmade coarse pottery is a lot more mobile than fine ceramics.
The coarse ware, which may have served to transport preserved food, traces a (supra-) regional trade system whose significance
is often forgotten next to Mediterranean imports (amphorae, tableware).