"Normally, we can place the age of wood by comparing the pattern of the growth rings with catalogued patterns from trees of known age, but your sample was too small for a dedrochronological analysis. The standard dating technique for organic material is a radiometric analysis using carbon 14 It is based on a comparison between the amount of carbon 14 remaining in the sample to the known ratio for living organisms, a fairly constant value. There are some variations in the ratio over time, so there are some correction factors to be applied, but in general, the method is quite accurate. The analysis was quite simple, but I didn't believe the results at first because the wood seemed so recent."