Radiometric dating zircon crystals peter mensch dating
Uranium minerals themselves are too uncommon to be very useful in dating.
The most common dating method involves the use of minerals like zircon and monazite that are relatively common in granitic rocks.
To see how we actually use this information to date rocks, consider the following: Usually, we know the amount, N, of an isotope present today, and the amount of a daughter element produced by decay, D*.
By definition, D* = N-1) (2) Now we can calculate the age if we know the number of daughter atoms produced by decay, D* and the number of parent atoms now present, N.
However, there have been concerns over the accuracy of using this method to date zircon crystals, which means there has been uncertainty about the exact age of the Jack Hills sample.
Uranium 235 decays to lead 207, and Thorium 232 decays to lead 208.
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.
In addition, some of the longer-lived intermediate daughter products have uses in dating.