The decay constants for most of these systems have been confirmed in other ways, adding strength to our argument for the age of the earth., so there is one zirconium (Zi) for one silicon (Si) for four oxygen (O).
One of the elements that can stand in chemically for zircon is uranium.
We have dated meteorites using Rb-Sr, Sm-Nd, Pb-Pb, Re-Os, and Lu-Hf isotope systems and have obtained very similar ages.
It is an accurate way to date specific geologic events.Hope that helps, and please ask if you'd like more details! I think that I will start by answering the second part of your question, just because I think that will make the answer to the first question clearer.Radiometric dating is the use of radioactive and radiogenic (those formed from the decay of radioactive parents) isotopes (isotopes are atoms of the same element that have different numbers of neutrons in their nuclei) to determine the age of something.The process of radiogenic dating is usually done using some sort of mass spectrometer.A mass spectrometer is an instrument that separates atoms based on their mass.