Chemical composition and sample preparation of archaeological wood for radiocarbon dating

Abstract

The chemical composition of wood from archaeological sites differs from that of modern wood. The chemical changes depend on the microenvironment of the surrounding matrix more than the time of preservation. Chemical treatment of decomposed wood results in a great loss of initial material. The degree of wood decomposition should be taken into account in the preparation of samples for 14C dating. The main fraction of archaeological decomposed wood is a degraded lignin, with most cellulose totally decomposed. Nevertheless, decomposed wood can be a reliable material for 14C dating archaeological sites. Loss of material through sample preparation can be reduced by using fairly weak concentrations of chemical reagents without influencing the reliability of the dates.