Carbon dating so frequently used archaeology
For periods without a historic record, attempts have been made to categorize tool kits, pottery styles, and architectural forms into regional timelines.
Some ill-fated attempts to define time even attempted to count backwards through the genealogies of the Bible, establishing a series of dates which remain a cause of confusion.
Upon death, the isotope begins to decay and after 5730±40 years half of it is gone.
The C-14 method cannot be used on material more than about 50,000 years old because of this short half-life.
Other isotopes are used by geologists to date older material.
In contrast to relative dating techniques whereby artifacts were simply designated as "older" or "younger" than other cultural remains based on the presence of fossils or stratigraphic position, 14C dating provided an easy and increasingly accessible way for archaeologists to construct chronologies of human behavior and examine temporal changes through time at a finer scale than what had previously been possible.
The application of Accelerator Mass Spectrometry (AMS) for radiocarbon dating in the late 1970s was also a major achievement.