As a result it is always undergoing natural radioactive decay while the abundances of the other isotopes are unchanged.
How carbon dating dirty lovers dating
They have masses of 13 and 14 respectively and are referred to as "carbon-13" and "carbon-14." If two atoms have equal numbers of protons but differing numbers of neutrons, one is said to be an "isotope" of the other.
Carbon-13 and carbon-14 are thus isotopes of carbon-12.
This would seem reasonable for a medieval nobleman, and certainly for a member of the royal family.
Allowing for this factor, and bearing in mind that the results cannot be later than 1538, a Bayesian statistic modelling technique gives the approximate date as AD1475-1530 (with a 69% confidence).
The rate at which C atoms, half of them will decay in 5730 years.