Carbon 14 radiometric dating is used for
And the result of this accepted method dates dinosaur fossils to around 68 million years old. Its half-life ($t_$) is only 5,730 years—that is, every 5,730 years, half of it decays away.
Materials useful for radiometric dating have half lives from a few thousand to a few billion years.If dinosaur bones are 65 million years old, there should not be one atom of C-14 left in them.Dinosaurs are not dated with Carbon-14, yet some researchers have claimed that there is still Carbon-14 in the bones. Do these data indicate that a more accurate method needs to be derived?That included protecting the samples, avoiding cracked areas in the bones, and meticulous pre-cleaning of the samples with chemicals to remove possible contaminants.
Knowing that small concentrations of collagen can attract contamination, they compared precision Accelerator Mass Spectrometry (AMS) tests of collagen and bioapatite (hard carbonate bone mineral) with conventional counting methods of large bone fragments from the same dinosaurs.
In addition, the initial element and the decay product should not be produced or depleted in significant amounts by other reactions.