T04_P20

A Brief History of Sulfur Isotope Analysis in Archaeological Bone Collagen at the SUERC Radiocarbon Laboratory.

Sayle K¹, Dunbar E², Hamilton D³

¹University of Glasgow, SUERC, East Kilbride, Scotland, ²University of Glasgow, SUERC, East Kilbride, Scotland, ³University of Glasgow, SUERC, East Kilbride, Scotland

The use of multi-isotopic analysis (δ¹⁵N, δ¹³C and δ³⁴S) of archaeological bone collagen to assist in the interpretation of diet, movement and mobility of prehistoric populations has been gradually increasing. Sulfur analysis has proven to be an extremely valuable additional tool for distinguishing between individuals who have obtained their food from terrestrial, marine and/or freshwater resources, which in turn can affect their radiocarbon ages.

Sulfur concentrations in bone collagen are generally very low (ca. 0.2–0.3%) compared to nitrogen and carbon concentrations (ca. 15% and 40%, respectively). This has presented an analytical challenge for simultaneous δ¹⁵N, δ¹³C and δ³⁴S analysis and resulted in the need to analyse one sample for δ¹⁵N and δ¹³C and a second, larger sample, for δ34S to obtain sufficient signals and data precision. Consequently, this led to longer analytical times and higher costs.

Recent advances in Elemental Analysis Isotope Ratio Mass Spectrometry (EA-IRMS) have opened up the potential for rapid, accurate and precise analysis at concentrations less than 10 µg of sulfur, whilst simultaneously acquiring data for and δ¹⁵N and δ¹³C, meaning samples can be analysed more rapidly and at a lower cost. Furthermore, depending on preservation, significantly smaller amounts of bone is required for analysis, and hence, less archaeological material is destroyed.

This poster will chart the development of sulfur isotope analysis in archaeological bone collagen at the SUERC Radiocarbon Laboratory over the past decade.