I'm not reading unsupported statements, I'm reading about the results of research that was conducted. "Both research teams used instruments called ion microprobes to date and analyze the zircon crystals, which often contain uranium, rare earth elements and other impurities. Uranium decays to lead at a known rate. Uranium-lead ratios in the zircons showed they formed as early as 4.4 billion to 4.3 billion years ago when they crystallized in molten granite"
OK, so how do they know what the original saturation of the "uraniam, rare earth elements and other impurities" were?
And how do they know that the present "known rate" has always been the same?
Exactly what I would have asked. I like to use the analogy of a burning candle.
You walk into a room and see a burning candle. Now you can measure how much of the candle is left and how much wax melts each minute, however how from these two things can you determine how long it has been burning for? In order to claim as much you need to know the initial height of the candle so then you can apply the rate of wax melted per minute in order to give an estimate of time. This is the same in that we do not know the initial amount of radioisotopes in the item hence radioactive dating simply is debunked on this basis alone. (We do not know the initial amount since we were not there to take a sample at the beginning of the universe, or the formation of the "ancient" rocks...)
However there is a way from the candle to work out how long it has been burning and that is to get an estimate of the wax that has been melted and then apply that retrospectively with the rate to see how long it would have taken to melt the wax that is presently melted... Now this is what the RATE team has done with helium in zircon crystals. Helium is a byproduct of uranium decay, (so in my analogy it is the byproduct that is the melted candle wax), and from this data the age of the earth is around 6000 years...
Read the book I mentioned, "thousands not millions" it is based on this evidence.