What is uranium 235 dating
In addition, some of the longer-lived intermediate daughter products have uses in dating.Uranium minerals themselves are too uncommon to be very useful in dating.In addition there is another stable isotope, lead 204, that is entirely primordial and does not form via radioactive decay at all.Thus any of the radioactive isotopes and its lead daughter product can be used for dating, or a combination may be used.
Uranium comes in two common isotopes with atomic weights of 235 and 238 (we'll call them 235U and 238U).
What makes this fact useful is that they occur at different rates, as expressed in their half-lives (the time it takes for half the atoms to decay).
The 235U–207Pb cascade has a half-life of 704 million years and the 238U–206Pb cascade is considerably slower, with a half-life of 4.47 billion years.
Uranium 238 decays through a series of steps to Lead 206.
Uranium 235 decays to lead 207, and Thorium 232 decays to lead 208.