So let me draw the Earth. Water molecules containing oxygen are lighter and therefore evaporate faster than water molecules with oxygen Teachers Love Study. Many labs now use an Accelerator Mass Spectrometer AMSa machine that can detect and measure the presence of different isotopes, to count the individual 14 C atoms in a sample. That's it. What he did not say is that those were winnowed out of tens of thousands of radiometric dates which do give more reasonable results. But we have more than that.
Radiometric Dating: Methods, Uses & the Significance of Half-Life
Obviously, the major question here is "how much of the isotope was originally present in our sample?
Carbon 14 dating 1
It's just a little section of the surface of the Earth. This means its nucleus is so large that it is unstable. They both form compounds readily and hold onto other atoms tenaciously.