Of the analysed material from Resmo, Köpingsvik and Torsborg, 53 human and 18 faunal bone and dentine samples fall outside the acceptable ranges for δ34S analysis with regard to %S, C/S and N/S (cf. Nehlich and Richards 2009). These samples are reported in Table 5, together with human samples from three additional Neolithic and Bronze Age sites on Öland (previously analysed with regard to δ13C and δ15N, see Eriksson et al. 2008), where no samples met the quality requirements. There is no correlation between %S and δ34S and accordingly no indications that the δ34S values have been affected by post-depositional contamination (cf. Kinaston et al. 2013).
In total, 70 human and 38 faunal samples fulfil the quality criteria with regard to %S, C/S and N/S, as suggested by Nehlich and Richards (2009). These include seven human and four faunal samples (highlighted by an asterisk in Table 2 and Table 3) which have been included as their values (either only %S or only N/S) fall within the desired ranges when corrected for weighing errors on the analytical balance. The only fish, a garpike, has a C/S ratio of 246, outside the stipulated range of 125-225 for fish. However, this range was established using a dataset that is heavily biased towards cod (>90% of the dataset: 89 out of 98 modern samples and 39 out of 42 historic samples) (Nehlich and Richards 2009). The bones of garpike, unlike cod, have a bluish-green colour, recently identified as biliverdin, associated with higher proportions of hydroxyproline (Jüttner et al. 2013), which could account for the relatively low sulphur concentration and thus elevated C/S ratio. Given the distinctive nature of garpike bone, it is therefore conceivable that the quality criteria for fish suggested by Nehlich and Richards (2009) may not be applicable. The sample has accordingly been included.
Internet Archaeology is an open access journal. Except where otherwise noted, content from this work may be used under the terms of the Creative Commons Attribution 3.0 (CC BY) Unported licence, which permits unrestricted use, distribution, and reproduction in any medium, provided that attribution to the author(s), the title of the work, the Internet Archaeology journal and the relevant URL/DOI are given.
File last updated: Thu Nov 13 2014