Potassium argon dating half life
Ar total fusion measures ratios, making it ideal for samples known to be very argon retentive (eg. Total fusion is performed using a laser and results are commonly plotted on probability distribution diagrams or ideograms.
Additional advantages of the single isotopic measurements of the K.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.Traditionally, this primary standard has been a hornblende from the Mc Clure Mountains, Colorado (a.k.a. Once an accurate and precise age is determined for the primary standard, other minerals can be dated relative to it by the Ar technique (e.g. However, while it is often easy to determine the age of the primary standard by the K/Ar method, it is difficult for different dating laboratories to agree on the final age.Likewise, because of heterogeneity problems with the MMhb-1 sample, the K/Ar ages are not always reproducible.