Systems that have been exploited for radiometric dating have half-lives ranging from only about 10 years (e.g., tritium) to over 100 billion years (e.g., Samarium-147). However, in general, the half-life of a nuclide depends solely on its nuclear properties and is essentially a constant.

Does radioactive dating tell age in number of years?

The abundances of parent and daughter isotopes in a sample can be measured and used to determine their age. This method is known as radiometric dating. The rate of decay for many radioactive isotopes has been measured and does not change over time.

Does radiometric dating use half life?

Nuclides useful for radiometric dating have half-lives ranging from a few thousand to a few billion years. The half-life of any nuclide is believed to be constant. Rubidium-strontium dating is based on the beta decay of rubidium-87 to strontium-87, with a half-life of 50 billion years.