How are we able to find fresh radioactive materials

Question

How can we be mining for radio active material if the earth was formed so long ago, would these materials not have run the course of depletion already? or is man kind creating them ? like Uranium or Plutonium

In: Chemistry

Answer 1

Uranium has a half-life of roughly 4.5 billion years. So the 10 pound chunk of uranium that was there when the earth was formed, is still a 5 pound chunk today.