Browsing Radiocarbon, Volume 43, Number 2A (2001 by Authors
Radiocarbon Dating of Single Compounds Isolated from Pottery Cooking Vessel ResiduesStott, A. W.; Berstan, R.; Evershed, P.; Hedges, Robert E. M.; Bronk Ramsey, Christopher; Humm, M. J. (Department of Geosciences, The University of Arizona, 2001-01-01)We have developed and demonstrated a practical methodology for dating specific compounds (and octadecanoic or stearic acid—C18:0—in particular) from the lipid material surviving in archaeological cooking pots. Such compounds may be extracted from about 10 g of cooking potsherd, and, after derivatization, can be purified by gas chromatography. To obtain sufficient material for precise dating repetitive, accumulating, GC separation is necessary. Throughout the 6000-year period studied, and over a variety of site environments within England, dates on C18:0 show no apparent systematic error, but do have a greater variability than can be explained by the errors due to the separation chemistry and measurement process alone. This variability is as yet unexplained. Dates on C16:0 show greater variability and a systematic error of approximately 100-150 years too young, and it is possible that this is due to contamination from the burial environment. Further work should clarify this.