These each have 19 protons and 21 neutrons in their nucleus.
If one of these protons is hit by a beta particle, it can be converted into a neutron.
The quantity of potassium in a rock or mineral is variable proportional to the amount of silica present.
Therefore, mafic rocks and minerals often contain less potassium than an equal amount of silicic rock or mineral.
Potassium decays into argon gas with a half-life of 1.251 billion years (we will round it up to 1.3 to keep things simple).
That means, in 1.3 billion years, half of a potassium sample with decay to argon gas.
Furthermore, there would be no way of knowing, because the Ar not from radioactive decay, except of course by external assumptions about the ages of the rocks.
For more than three decades potassium-argon (K-Ar) and argon-argon (Ar-Ar) dating of rocks has been crucial in underpinning the billions of years for Earth history claimed by evolutionists. Lassen plagioclase, California (AD 1915) 0.11±0.03 Ma Sunset Crater basalt, Arizona (AD 1064-1065) 0.27±0.09 Ma; 0.25±0.15 Ma Akka Water Fall flow, Hawaii (Pleistocene) 32.3±7.2 Ma Kilauea Iki basalt, Hawaii (AD 1959) 8.5±6.8 Ma Mt.
Critical to these dating methods is the assumption that there was no radiogenic argon ( Hualalai basalt, Hawaii (AD 1800-1801) 1.6±0.16 Ma; 1.41±0.08 Ma Mt. Stromboli, Italy, volcanic bomb (September 23, 1963) 2.4±2 Ma Mt.
Thus all K-Ar and Ar-Ar "dates" of volcanic rocks are questionable, as well as fossil "dates" calibrated by them.
Ar Analyses of Historic Lava Flows.” Nevertheless, this is no way changes the argument in question.