The re-dating of some Scottish specimens by the Oxford Radiocarbon Accelerator Unit (ORAU)

The purpose of this note is to alert readers to the fact that some AMS dates determined by ORAU on Scottish material between 2000 and 2002 have had to be deleted and re-determined, because of a problem in the ultrafiltration system used to pretreat bone samples during that period (see C Bronk Ramsey, T Higham, A Bales and R Hedges 2004, Improvements in the pretreatment of bone at Oxford, Radiocarbon 46(1), 155–63, for details). In many cases it has been possible to undertake the re-dating using left over material from the original (unprocessed) samples; in other cases, re-sampling will be necessary. Lists of both sets of material are appended here, and readers are requested to use only the new dates, and to delete the old versions.