Identifying Eadgyth

When German archaeologists discovered bones in the tomb of Queen Eadgyth in Magdeburg Cathedral, they looked to Bristol to provide the crucial scientific evidence that the remains were indeed those of the English royal. Dr Alistair Pike in the Department of Archaeology and Anthropology tells Hannah Johnson how tiny samples of tooth enamel proved the identity of a Saxon queen. Teeth provide remarkable evidence about the early years of an individual's life. The region where a person grew up can be traced in the tooth enamel laid down in their first 14 years because strontium and oxygen isotope ratios in the teeth reflect the food a person ate and the water they drank. When rocks form, they contain minute traces of radioactive rubidium 87, which decays to strontium 87. Over millions of years, the ratio of strontium 87 to the stable isotope strontium 86 changes, so, in very young rocks, the ratio will be smaller than in very old rocks. These rocks weather and become the soils where animals are grazed and crops grown.