Plant macro-remains preserved in slag-pit furnaces from the Iron-Age settlement in the Mazovian Centre of Metallurgy

Iron production appeared in the Barbarian World in the Early pre-Roman Iron Age (5th–3rd c. BC), but in the study area, in Central Poland, the exact timing has not been well recognised yet due to the absence of distinctive artefacts in the archaeological record that are directly connected to metal production. The main purpose of this study was to investigate features archaeobotanically and analyse charred plant macro-remains from slag-pits. Among them, cultivated plants were almost absent, while plants growing in grasslands, meadows, and ruderal places dominated the assemblage. Most numerous were grasses producing small grains, though brome grass was also present. Members of the Polygonaceae family and fat-hen were significant while other small and rather delicate seeds and fruits were scarce. We noticed a similarity between our assemblage and the data coming from Iron-Age Jutland in present-day Denmark, but the latter differs in the composition of plant remains, which usually is dominated by crops and field weeds. In the case of the site at Zaborów, we can presume a similar use of herbal plants in smelting technology, but the local environment was probably different from that in Jutland. In Zaborów, open landscape dominated, covered by grasslands and ruderal plants, while the presence of crop fields was not confirmed yet. Preliminary radiocarbon data obtained from eight seed samples indicate that in the studied area, metal production started at least one century earlier than was previously assumed, probably introduced by settlers of the Jastorf culture originating from the Jutland Peninsula.