About radiocarbon dating

This method requires less than 1g of bone, but few countries can afford more than one or two AMSs, which cost more than A0,000.Australia has two machines dedicated to radiocarbon analysis, and they are out of reach for much of the developing world.Radioactive decay can be used as a “clock” because it is unaffected by physical (e.g. For instance, the amount varies according to how many cosmic rays reach Earth.This is affected by solar activity and the earth’s magnetic field.Radiocarbon dates are presented in two ways because of this complication.

Tree rings can be counted and their radiocarbon content measured.In 2008 we could only calibrate radiocarbon dates until 26,000 years.Now the curve extends (tentatively) to 50,000 years.The second difficulty arises from the extremely low abundance of C, making it incredibly difficult to measure and extremely sensitive to contamination.In the early years of radiocarbon dating a product’s decay was measured, but this required huge samples (e.g. Many labs now use an Accelerator Mass Spectrometer (AMS), a machine that can detect and measure the presence of different isotopes, to count the individual C atoms in a sample.