Small sample dating in China

The Xi'an Laboratory of Loess and Quaternary Geology has developed a small sample ¹⁴C dating facility consisting of a Wallac 1220 Quantulus^TM liquid scintillation spectrometer, and a miniature benzene synthesis line based on the synthesis procedures used at the Australian National University (ANU). This line can produce ca. 0.3-ml benzene samples, which are then measured for ¹⁴C activity using 0.3-ml Teflon vials developed by Wallac Oy. The counting performance of the Quantulus^TM spectrometer using 0.3-ml vials has been evaluated, and a potential age limit of ca. 45 000 BP has been obtained for samples containing up to 250 mg carbon. This dating facility fills the gap between large sample (2.4-6 g carbon) and microsample (<1 mg carbon) handling to form a ¹⁴C dating method sequence. -Authors