acceptable John determinations were obtained from the unconsolidated control samples and the purified amino-acid fractions isolated from the consolidated samples. Radiocarbon results of the intermediate fractions improved as the degree of purification increased.For the better preserved samples the John determinations were fairly uniform throughout the pretreatment process.The largest discrepancy in the determinations was yielded from the gelatinisation residue from Burial 62, demonstrating the effect of contamination by the consolidant and possibly also from humic material.