The methods work because radioactive elements are unstable, and they are always trying to move to a more stable state. This process by which an unstable atomic nucleus loses energy by releasing radiation is called radioactive decay.
Free 5-day trial Radiometric dating is used to estimate the age of rocks and other objects based on the fixed decay rate of radioactive isotopes.Learn about half-life and how it is used in different dating methods, such as uranium-lead dating and radiocarbon dating, in this video lesson. As we age, our hair turns gray, our skin wrinkles and our gait slows.So, we start out with two isotopes of uranium that are unstable and radioactive.They release radiation until they eventually become stable isotopes of lead.When the isotope is halfway to that point, it has reached its half-life.
There are different methods of radiometric dating that will vary due to the type of material that is being dated.
With rubidium-strontium dating, we see that rubidium-87 decays into strontium-87 with a half-life of 50 billion years.
By anyone's standards, 50 billion years is a long time.
With radiocarbon dating, the amount of the radioactive isotope carbon-14 is measured.
Compared to some of the other radioactive isotopes we have discussed, carbon-14's half-life of 5,730 years is considerably shorter, as it decays into nitrogen-14.
For example, uranium-lead dating can be used to find the age of a uranium-containing mineral.