The slope of the line determines the date, and the closeness of fit is a measure of the statistical reliability of the resulting date.Technical details on how these dates are calculated are given in Radiometric dating. As with any experimental procedure in any field of science, these measurements are subject to certain "glitches" and "anomalies," as noted in the literature.Carbon dating is used to determine the age of biological artifacts up to 50,000 years old.This technique is widely used on recent artifacts, but educators and students alike should note that this technique will not work on older fossils (like those of the dinosaurs alleged to be millions of years old).The age of the carbon in the rock is different from that of the carbon in the air and makes carbon dating data for those organisms inaccurate under the assumptions normally used for carbon dating.
Radiometric dating is self-checking, because the data (after certain preliminary calculations are made) are fitted to a straight line (an "isochron") by means of standard linear regression methods of statistics.
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.
Levels of carbon-14 become difficult to measure and compare after about 50,000 years (between 8 and 9 half lives; where 1% of the original carbon-14 would remain undecayed).
The question should be whether or not carbon-14 can be used to date any artifacts at all? There are a few categories of artifacts that can be dated using carbon-14; however, they cannot be more 50,000 years old.