

This technique is not restricted to bones; it can also be used on cloth, wood and plant fibers. Carbon14 dating has been used successfully on the Dead Sea Scrolls, Minoan ruins and tombs of the pharaohs among other things. The halflife of carbon14 is approximately 5,730 years. dinosaurs the evolution alleges lived millions of years ago. Carbon14 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.


Thereafter, the concentration (fraction) of 14C declines at a fixed exponential rate due to the radioactive decay of 14C. ) Comparing the remaining 14C fraction of a sample to that expected from atmospheric 14C allows us to estimate the age of the sample.Radiocarbon dating (usually referred to simply as carbon14 dating) is a radiometric dating method.It uses the naturally occurring radioisotope carbon14 (14C) to estimate the age of carbonbearing materials up to about 58,000 to 62,000 years old.Scientists use a technique called radiometric dating to estimate the ages of rocks, fossils, and the earth.Many people have been led to believe that radiometric dating methods have proved the earth to be billions of years old.Protons and neutrons make up the center (nucleus) of the atom, and electrons form shells around the nucleus.The number of protons in the nucleus of an atom determines the element.The method of carbon dating makes use of the fact that all living organisms contain two isotopes of carbon, carbon12, denoted 12C (a stable isotope), and carbon14, denoted 14C (a radioactive isotope).The ratio of the amount of 14C to the amount of 12C is essentially constant (approximately 1/10,000).A fossil found in an archaeological dig was found to contain 20% of the original amount of 14C. I do not get the $0.693$ value, but perhaps my answer will help anyway.If we assume Carbon14 decays continuously, then $$ C(t) = C_0e^, $$ where $C_0$ is the initial size of the sample. Since it takes 5,700 years for a sample to decay to half its size, we know $$ \frac C_0 = C_0e^, $$ which means $$ \frac = e^, $$ so the value of $C_0$ is irrelevant.
