Metamorphic processes invalidate radiometric dating methods
Each such age would match the result given by the isochron.
Gain or loss of In order to make the figures easy to read (and quick to draw), the examples in this paper include few data points.
Unfortunately, one must wade through some hefty math in order to understand the procedures used to fit isochron lines to data.
(This topic will be discussed in much more detail below.) Where the simple methods will produce an incorrect age, isochron methods will generally indicate the unsuitability of the object for dating.
There are minor differences between isotopes of the same element, and in relatively rare circumstances it is possible to obtain some amount of differentiation between them. The effect is almost always a very small departure from homogeneous distribution of the isotopes -- perhaps enough to introduce an error of 0.002 half-lives in a non-isochron age. but it is rare and the effect is not large enough to account for extremely old ages on supposedly young formations.) as minerals form.
This results in a range of X-values for the data points representing individual minerals.
Age "uncertainty" When a "simple" dating method is performed, the result is a single number.
There is no good way to tell how close the computed result is likely to be to the actual age.