Radiometric dating easy definition
One problem is that potassium is also highly mobile and may move into older rocks.This depends on the decay of uranium-237 and uranium-238 to isotopes of lead.The oldest rock so far dated is a zircon crystal that formed 4.4-billion-years ago, which was only 200 million years or so after the Earth itself formed.YEC biblical literalists are necessarily bound to the dogmatic religious conclusion that the Earth is of a certain age based on a particular literal interpretation of the Genesis creation myth.
Carbon-14 decays almost completely within 100,000 years of the organism dying, and many fossils and rock strata are hundreds of times older than that.
We can measure directly, for example by using a radiation detector, and obtain a good estimate of by analyzing the chemical composition of the sample.
The half-life , specific to each nuclide, can be accurately measured on a pure sample, and is known to be independent of the chemical composition of the sample, temperature and pressure.
Due to the long half-life of uranium it is not suitable for short time periods, such as most archaeological purposes, but it can date the oldest rocks on earth.
A proper radiometric date should read years before present (with 1950 being present) ± range/2 at x standard deviations (Xσ)', but is often reported as a single year or a year range, like 1260–1390 CE (the date for the Shroud of Turin).