But the almost tenfold increase in atmospheric C14 that peaked around the mid-1960s has been followed by a rapid decline since the nuclear test ban treaties and the cessation of high-yield, above-ground nuclear tests.In fact, C14 is assimilated so rapidly that from about 1963, its half-life in the atmosphere has only been about 11 years.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.But yes, for any form of destructive testing, such as radiocardon dating, they usually use other methods to gauge the age of the artifact or specimen.
In general, 500 years is the minimum and 50,000 years is the maximum due to the need to calibrate for background C-14 levels, and to have sufficient breakdown to establish the half-life proportions but not so much that the sample is too small to measure.This technique is not restricted to bones; it can also be used on cloth, wood and plant fibers.Carbon-14 dating has been used successfully on the Dead Sea Scrolls, Minoan ruins and tombs of the pharaohs among other things. The half-life of carbon-14 is approximately 5,730 years. dinosaurs the evolution alleges lived millions of years ago.Carbon-14 cannot be used to date biological artifacts of organisms that did not get their carbon dioxide from the air.This rules out carbon dating for most aquatic organisms, because they often obtain at least some of their carbon from dissolved carbonate rock.