These dating techniques, which are firmly grounded in physics and are known collectively as radiometric dating, are used to measure the last time that the rock being dated was either melted or disturbed sufficiently to rehomogenize its radioactive elements. There are more than 70 meteorites, of different types, whose ages have been measured using radiometric dating techniques.
The best age for the Earth is carbon dating credible not from dating individual rocks but by considering the Earth and meteorites as part of the same evolving system in which the isotopic composition of lead, specifically the ratio of lead to lead changes over time owing to the decay of radioactive uranium and uraniumrespectively.
For this reason, it's preferable to date objects using multiple methods, rather than relying on one single test. Carbon dating is reliable within certain parameters.