Because C-14 dating uses the decay rate of Carbon 14 as its measure (more on this later), this gives upper and lower limits to the dating method. This means that the upper limit of C-14 dating is currently around 50,000 years ago.
What is the maximum range for accurate radiocarbon dating?
When Libby first presented radiocarbon dating to the public, he humbly estimated that the method may have been able to measure ages up to 20,000 years. With subsequent advances in the technology of carbon-14 detection, the method can now reliably date materials as old as 50,000 years.
What are the limits on radiometric dating?
Radiometric dating is a very useful tool, but it does have limits: The material being dated must have measurable amounts of the parent and/or the daughter isotopes. Radiometric dating can be done on only some materials. It is not useful for determining the age of sedimentary rocks.