Carrara marble used to estimate correction for sample preparation background contamination. pMC represents ratio of radiocarbon content of sample normalised to that in Oxalic acid standard (OX-I). Final pMC values obtained after normalisation to Oxalic standard, mass and 13C correction, and chemistry background. Ages given as conventional radiocarbon ages, not calendar ages. Limiting ages and that for NDFB (not distinguishable from background) determined according to Stuiver & Polach (1977).