Lead (Pb) isotope signatures for silcrete sources from the Willandra Lakes region, Australia: A pilot study of a new method for provenancing silcrete artefacts

Holocene and recent aeolian reactivation of the Willandra Lakes lunettes, semi-arid southeastern Australia

“…We investigated the question of mobility by comparing the chipped stone artefacts found in the post-lake aeolian sediments (Unit F) with those found in the underlying Last Glacial Maximum (LGM) age sediments (Unit E/Zanci; Table S8, available online; Figure S7, available online). The only sources of raw material in the Willandra Lakes region suitable for tool-making originate from numerous outcrops of silcrete located within 5–80 km of the central Mungo lunette and 2 of quartzite located 30–80 km away; thin section, trace element and Pb-isotope analyses have been used to characterise the silcrete sources (Kurpiel, 2017; Kurpiel et al, 2019). During both time periods, most of the material for making tools was obtained from the silcrete outcrops, but after the lake dried out, greater use was made of the higher-quality quartzite, suggesting that these localised and more distant sources of material were visited more often.…”

“…Taken together, these features of the Unit F chipped stone assemblage suggest that once the lakes dried out, people made greater use of raw material from relatively distant sources and placed greater emphasis on provisioning individuals with tools and highly portable cores than provisioning the landscape with raw material. In contrast, the LGM assemblages from the same part of the lunette suggest that provisioning the landscape with raw material was the predominant strategy employed at that time (Kurpiel, 2017). suggests that people were more mobile after the lakes dried out, and that a change in stone technology was one of the ways in which they responded to the altered environmental conditions.…”

Lead isotopic compositions link copper axes from Kietrz (Poland, 3500–3350 BC) to Slovak and Balkan copper mines

“…Lead isotope data were acquired under clean‐room conditions at the University of Melbourne (e.g., Kurpiel et al, 2019; Maas et al, 2015) using multi‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS). Small splits (5–15 mg) of Cu filings drilled from the copper axes (hand‐held electric drill, Pb‐free steel dental drill bits, new drill bit for each sample) were dissolved in concentrated HNO 3 (2 mL) and heated in capped Savillex beakers overnight (100°C); all produced blue solutions with minor residue.…”