Can We “Play Dirty” in ESR Dating?

Electron spin resonance (ESR) dating is currently one of the major dating techniques in archaeology, paleoanthropology, and paleontology. Years of experience have led to some standard protocols for ESR dating. However, these limit studies because some tooth enamel samples fail the criteria in the protocols. One criterion is that the enamel must be completely free of dentine. There are tooth fragments that are so small that complete cleaning would not leave enough enamel for dating. To see if this standard protocol is absolutely required, several samples of “dirty” enamel were compared. The results confirm the need for essentially complete cleaning.