Carbon-14 dating does not produce ages in the millions of years, as do some other types of radioisotope dating.
C dating consists of measuring the amounts of carbon-14 and carbon-12, and sometimes C-13, in a sample.
In practice, there are sufficient variations in these conditions that it is necessary to correct a sample’s raw radiocarbon age by comparing it with the standard calibration curve.
Carbon-14 dating depends on the amount of atmospheric carbon-14 relative to carbon-12.
Int Cal09 and Marine09 radiocarbon age calibration curves, 0-50,000 years cal BP.  This was the scroll “Testament of Qahat,” for which the radiocarbon date was about two centuries older than the date based on paleography.
Radiocarbon dating is one of the most widely used scientific dating methods in archaeology and environmental science.
Another assumption is that the amounts of carbon-14 present in the geophysical reservoirs must be constant.In most cases, the three methods produced similar results.Surprisingly, in at least one case the date range given by There may be other examples of systematic variation in isotope decay rates. It is widely used in dating fossils or archaeological samples containing organic material such as wood, charcoal, bone, shells, etc.It is not used to date rocks or other inorganic material.