In most cases, the half-life of a nuclide depends solely on its nuclear properties; it is not affected by temperature, chemical environment, magnetic and electric fields, or any other external factors.
The half-life of any nuclide is also believed to be constant through time.
If a material that selectively rejects the daughter nuclide is heated, any daughter nuclides that have been accumulated over time will be lost through diffusion, setting the isotopic "clock" to zero.
The possible confounding effects of initial contamination of parent and daughter isotopes have to be considered, as do the effects of any loss or gain of such isotopes since the sample was created.
Additionally, elements may exist in different isotopes, with each isotope of an element differing only in the number of neutrons in the nucleus.
A particular isotope of a particular element is called a nuclide. That is, at some random point in time, an atom of such a nuclide will be transformed into a different nuclide by the process known as radioactive decay.
Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances.
Various methods exist differing in accuracy, cost and applicable time scale All ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus.