ESR dating of tooth enamel from prehistoric archaeological sites

Electron spin resonance (ESR) can be used to date hydroxyapatite of tooth enamel, a common component of prehistoric archaeological sites. Dates, ranging from 10 ka to ∼ 3Ma, are calculated from the accumulated radiation dose, A, and the dose rate, D, which varies with time as a result of uptake of U and growth of U-daughters to secular equilibrium.