Radiocarbon dating is one kind of radiometric dating, used for determining the age of organic remains that are less than 50,000 years old.
For inorganic matter and for older materials, isotopes of other elements, such as potassium, uranium, and strontium, are used.
A new, more stable isotope, called the decay or daughter product, takes its place.
Scientists look at half-life decay rates of radioactive isotopes to estimate when a particular atom might decay.
However, rocks and other objects in nature do not give off such obvious clues about how long they have been around.
A useful application of half-lives is radioactive dating.
This has to do with figuring out the age of ancient things.
The amount of the isotope in the object is compared to the amount of the isotope's decay products.
The object's approximate age can then be figured out using the known rate of decay of the isotope.