Pretreatment and gaseous radiocarbon dating of 40–100 mg archaeological bone

Abstract

Radiocarbon dating archaeological bone typically requires 300–1000 mg material using standard protocols. We report the results of reducing sample size at both the pretreatment and 14 C measurement stages for eight archaeological bones spanning the radiocarbon timescale at different levels of preservation. We adapted our standard collagen extraction protocol specifically for <100 mg bone material. Collagen was extracted at least twice (from 37–100 mg material) from each bone. Collagen aliquots containing <100 μg carbon were measured in replicate using the gas ion source of the AixMICADAS. The effect of sample size reduction in the EA-GIS-AMS system was explored by measuring 14 C of collagen containing either ca . 30 μg carbon or ca . 90 μg carbon. The gas dates were compared to standard-sized graphite dates extracted from large amounts (500–700 mg) of bone material pretreated with our standard protocol. The results reported here demonstrate that we are able to reproduce accurate radiocarbon dates from <100 mg archaeological bone material back to 40,000 BP.

New perspectives on Neanderthal dispersal and turnover from Stajnia Cave (Poland)

“…The collagen for the 5 animal bones and the S5000 tooth were extracted at the Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig (Germany) following the pretreatment procedures in Talamo and Richards 54 and Fewlass, et al 55 respectively.…”

“…Due to the limited material available, we extracted collagen from a very small sample of the S5000 tooth using the method described in 55 . Briefly, 70.5 mg dentine was removed with a dentistry drill and demineralised in HCl 0.5 M (4 °C) for one day.…”

The Zagros Epipalaeolithic revisited: New excavations and 14C dates from Palegawra cave in Iraqi Kurdistan

“…This suggests that the mixing and movement of material between spits and/or mistakes in sample labelling in the field are unlikely sources of error. Another potential source of error with Palaeolithic bone protein collagen samples dated before the advent of ultrafiltration pre-treatment methods, is that the collagen may contain low molecular weight contaminants of modern origin which will invariably result in systematically younger radiocarbon age determinations [ 45 – 47 ]. The possibility of modern contamination (from dirty excavation tools, cigarette ash or smoke, and packing materials such as cotton wool or paper) is high for samples excavated in the 1950s when appropriate field sampling protocols had not been developed yet.…”

“Here we go again”: the inspection of collagen extraction protocols for 14C dating and palaeodietary analysis

“…Initially, the protocol followed Richards and Hedges (1999) but was updated to include an additional step to purify the collagen with Ezee-filters and ultrafiltration (Sealy et al 2014). The second protocol (Method 2) has been in use since 2011 (Talamo and Richards 2011;Fewlass et al 2019) for the extraction of collagen specifically for radiocarbon dating Palaeolithic bone (e.g. Hublin et al 2012;Talamo et al 2012;Talamo et al, 2016a;Fewlass et al 2020;Talamo et al 2020).…”

“…For Experiment A, we used two samples: one mammoth bone (R-EVA 123) and one woolly rhino bone (R-EVA 124), both from the North Sea plain (Table 1). These samples have been widely used in methodological tests at the MPI-EVA (Talamo and Richards 2011;Fewlass et al 2018;Korlević, Talamo, and Meyer 2018;Fewlass et al 2019). For each bone, the outer surface was first cleaned by a shot blaster to eliminate impurities from the surface.…”