Carbon-14 dating techniques were first developed by the American chemist, Willard F.
Libby at the University of Chicago in the 50’s, for which he received the Nobel Prize in Chemistry in 1960.
I've been poking about on the internet again (as you do) and found a whole load of stuff by creationists about the problems with carbon 14 radiometric dating.
Specifically they report (with some glee) that coal has been found to contain measurable amounts of carbon14 which it should not of course because it is about 300 million years old and dates from the carboniferous period.
Carbon is naturally in all living organisms and is replenished in the tissues by eating other organisms or by breathing air that contains carbon.
At any particular time all living organisms have approximately the same ratio of carbon 12 to carbon 14 in their tissues.
C14 has a half life of 5730 years and is only good to date objects to 50,000 years or so.
Although I can find any number of references to this seemingly vital finding on the creationist sites, I can find almost no attempt to refute or explain this anomaly on serious science sites. There seem to be some unsubstantiated references to the possibility of neutrons generated by uranium decay resulting in an anomalously high presence of C14.The problem: If the material is too old, the small amount of C14 present may not decay in the measurement interval. Nearby radioactive material could trigger exactly the same C14 production process from nitrogen as occurs in the upper atmosphere, albeit at a much reduced rate.Newer, more accurate techniques use mass spectroscopy. It doesn't take much contamination to spoil a sample with near-zero quantity of C14. Another possible avenue is C13, which has a small but non-zero neutron absorption cross section.Radiocarbon dating can be used on samples of bone, cloth, wood and plant fibers.The half-life of a radioactive isotope describes the amount of time that it takes half of the isotope in a sample to decay.About 21 pounds of Nitrogen is converted each year making about 1/trillion atmospheric carbon atoms radioactive C.