However, the Argon, a noble gas, constitutes approximately 0.1-5% of the Earth's present day atmosphere.
Because it is present within the atmosphere, every rock and mineral will have some quantity of Argon.
Ca F is also routinely irradiated and measured to determine the Ar technique relies on ratios instead of absolute quantities, we are able to extract and measure multiple aliquots of argon from a single sample.
Multiple argon extractions can be performed on a sample in several ways.
J value uncertainty can be minimized by constraining the geometry of the standard relative to the unknown, both vertically and horizontally.
The NMGRL does this by irradiating samples in machined aluminum disks where standards and unknowns alternate every other position.
Because the J value is extrapolated from a standard to an unknown, the accuracy and precision on that J value is critical.
Argon loss occurs when radiogenic K by a fast neutron reaction) can be used as a proxy for potassium.
Therefore, unlike the conventional K/Ar technique, absolute abundances need not be measured.
For the J to be determined, a standard of known age must be irradiated with the samples of unknown age.
Because this (primary) standard ultimately cannot be determined by Ar, it must be first determined by another isotopic dating method.The monitoring of the interfering reactions is performed through the use of laboratory salts and glasses.