In theory, it might be useful to archaeology, but not to geology or paleontology.
And second, that the elements they were before and after the radioactive decay have different chemical properties. If an atom doesn’t interact chemically in the right way, then it won’t be incorporated into a forming crystal. Carbon dating is the most famous form of “radiometric dating”.By measuring the trace amounts of radioactive carbon-14 (so named because it has 6 protons and 8 neutrons) in a dead something and comparing it to the amount of regular carbon-12 (6 protons and 6 neutrons) you can figure out how long it’s been since that sample was alive.A less sophisticated word for midden is “pile of garbage and often poo”.Generally speaking, archaeologists make the assumption that if the grains in and around of a clay pot are, say, 8,000 years old, then the pot itself is roughly the same age. If you had an ancient amphora sitting around, would you use it for fresh strawberry preserves? A life spent potentially confusing future archaeologists is a life well spent.Obviously, if half the C-14 decays in 5,730 years, and half more decays in another 5,730 years, by ten half-lives (57,300 years) there would be essentially no C-14 left.