Glasgow University Radiocarbon Measurements IX

Abstract

The following date list presents results obtained during 1975-1977. The facilities at Glasgow have been further developed and include a gas counting system utilizing CO2 as counting material and two liquid scintillation counting laboratories based on synthesis of benzene. The results presented here were obtained using the liquid scintillation system only. Sample pretreatment varied according to individual sample type, whether wood or charcoal. The majority of samples were of preserved wood. After manual removal of gross contamination, samples of wood were finely chopped and digested in boiling, 2M KOH solution. The dehumified wood was then separated by filtration, thoroughly washed with distilled water and dilute hydrochloric acid, and then bleached in a solution of NaClO2/HCl at 80°C for 48 hours. Pure, white wood cellulose was obtained by filtration and washed with a large volume of distilled water. The cellulose, typically 40% by weight of the original material, was then dried overnight in an oven at 80°C. Samples of charcoal were closely examined for non-contemporaneous contamination and then subjected to successive treatments with hot, dilute (1M) KOH and HCL, respectively. The remaining charcoal was then dried overnight at 80°C.