It does, however, give a maximum age of the Earth. Skip to main content. This also assumes that there was no initial daughter isotopes contained in the magma at the time of cooling. Since K is one of the 10 most abundant elements in the Earth's crust, the decay of 40 K is important in dating rocks. If all of the age-dating methods rubidium-strontium, uranium-lead and potassium-argon had yielded the same ages, the picture would be neat.
This would make the observed haloes consistent with an old age for the coal.
The Iconic Isochron: Radioactive Dating, Part 2
An organism takes in small amounts of carbon, together with the stable nonradioactive isotopes carbon 12 C and carbon 13 Cas long as it is alive. Kohlhorster reported that potassium also emitted gamma radiation. Charcoal from the same level as that containing specimen 9 yielded a radiocarbon age of 5, years.