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.Uranium is not the only isotope that can be used to date rocks; we do see additional methods of radiometric dating based on the decay of different isotopes.For example, with potassium-argon dating, we can tell the age of materials that contain potassium because we know that potassium-40 decays into argon-40 with a half-life of 1.3 billion years.With rubidium-strontium dating, we see that rubidium-87 decays into strontium-87 with a half-life of 50 billion years.

So, you might say that the 'full-life' of a radioactive isotope ends when it has given off all of its radiation and reaches a point of being non-radioactive.

As a member, you'll also get unlimited access to over 79,000 lessons in math, English, science, history, and more.

Plus, get practice tests, quizzes, and personalized coaching to help you succeed.

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.

So, you might say that the 'full-life' of a radioactive isotope ends when it has given off all of its radiation and reaches a point of being non-radioactive.As a member, you'll also get unlimited access to over 79,000 lessons in math, English, science, history, and more.Plus, get practice tests, quizzes, and personalized coaching to help you succeed.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, how do we know that the Iceman, whose frozen body was chipped out of glacial ice in 1991, is 5,300 years old?