All of these processes may adversely affect isotopic dating mechanisms because the sample cannot always be assumed to have remained as a closed system, by which it is meant that either the parent or daughter nuclide a species of atom characterised by the number of neutrons and protons an atom contains or an intermediate daughter nuclide may have been partially removed from the sample, which will skew the resulting isotopic date. This is particularly true of uranium and lead. Within a few decades, most mainstream religious denominations accepted this view as well.
For example, he assumed that the samples had contained only uranium and no lead when they were formed. The quoted age of Earth is derived, in part, from the Canyon Diablo meteorite for several important reasons and is built upon a modern understanding of cosmochemistry built up over decades of research. The disintegration products of uranium". The slope of the line determines the age of the rock, and the closeness of fit is a measure of the statistical reliability of this conclusion.