Mechanical crushing is also a technique capable of releasing argon from a single sample in multiple steps.
Laser probes also allow multiple ages to be determined on a single sample aliquot, but do so using accurate and precise spatial control.
However, because each of these parameters is difficult to determine independantly, a mineral standard, or monitor, of known age is irradiated with the samples of unknown age.
The monitor flux can then be extrapolated to the samples, thereby determining their flux.
Likewise, because of heterogeneity problems with the MMhb-1 sample, the K/Ar ages are not always reproducible.
Argon can mobilized into or out of a rock or mineral through alteration Ar and potassium, there is not a reliable way to determine if the assumptions are valid.
Argon loss and excess argon are two common problems that may cause erroneous ages to be determined.
The monitoring of the interfering reactions is performed through the use of laboratory salts and glasses.
For example, to determine the amount of reactor produced Ar ratio of the glass is then measured in the mass spectrometer to determine the correction factor that must be applied to the rest of the samples in that irradiation.