AMS-dating of Sidon Archaeological Phases

Our samples for AMS-dating were obtained on short-lived organic material from secure and stratigraphically well-defined contexts. As secure contexts, we appraise archaeological assemblages that did not contain later archaeological material, i.e. ceramics that obviously intruded from later into earlier phases. Archaeologists involved in the excavation of multilayer settlements sites are aware of the appearance of residual material through reworking due to levelling and building activities, including the opening of pits. It was due to such activities that sparse pottery finds of Mycenaean type or origin appeared throughout the Early Iron Age stratigraphic sequence of Sidon. This applies in particular to our ¹⁴C-dated Phases C, D and E. It is not a coincidence that more than half of the Mycenaean and other Late Bronze Age pottery sherds from the site were found in just one room (Room 6), and this is the room that experienced the most extensive reworking. We also have instances of vessels that were reconstructed from sherds scattered throughout different phases. The large majority of the Early Iron Age contexts containing substantial residual ceramic material were not considered to have any value for the purpose of ¹⁴C-sampling.
To establish an absolute time-scale for Sidon Phases A-K we have at our disposal altogether 37 ¹⁴C-ages on (annual-growth) olive stones and (short-lived) animal bones (Table 1). A first set of ¹⁴C-ages were processed in the year 2017 on 29 olive stones and 3 bones at the Oxford ¹⁴C-AMS laboratory (Lab Code: OxA). A second set of ¹⁴C-ages on 5 bones were processed in 2018 at the Mannheim ¹⁴C-AMS laboratory (Lab Code: MAMS). The majority of ¹⁴C-ages have standard deviations of ± 30 BP or better. According to the information provided by the laboratories, the bone collagen was extracted using weak acid dissolution, followed by ultrafiltration and separation of the fraction > 30 kD. The extracted organic carbon was then dry-frozen and burnt in an Elemental Analyser to produce CO₂ which was catalysed to produce graphite. The charred olives were pre-treated using the standard ABA-method (Acid/Base/Acid; HCl/NaOH/HCl). By selectively dating olive stones (78%), whenever available, and with sampling extended to include short-lived animal bone (22%) when olive stones were not available, the idea is to avoid any kind of inbuilt ‘old wood’ effect that might be due to any perchance selection of inner tree-rings, reworked wood, or of recycled charcoal e.g. for domestic heating purposes. In consequence, potential outliers are most likely caused by stratigraphic reworking (olive stones), in addition to potential chemical alteration (bones).