Its crust is continually being created, modified, and destroyed.
However, had the original bones been available for study, this hoax would probably not have continued for as long as it did.
It was not until 38 years after the bones had been "found" that the hoax was exposed.
The skull was indeed human (about 500 years old) but the jaw was that of a modern ape whose teeth had been filed to look like human wear.
The success of this hoax for almost 40 years is pretty impressive.
It is readily admitted that many scientists believed in Piltdown Man wholeheartedly and made some rather foolish statements concerning the meaning of this "find." It is also admitted that Piltdown Man's general acceptance as a "missing link" was due to the fact that it matched the prevailing opinion of the time as to what such as missing link would look like.
Of course, the argument is that many scientists of the day did not think too much of Piltdown Man since many did not think that the cranium and the jaw were from the same creature.
The number of parent atoms originally present is simply the number present now plus the number of daughter atoms formed by the decay, both of which are quantities that can be measured.
Samples for dating are selected carefully to avoid those that are altered, contaminated, or disturbed by later heating or chemical events.
In addition to the ages of Earth, Moon, and meteorites, radiometric dating has been used to determine ages of fossils, including early man, timing of glaciations, ages of mineral deposits, recurrence rates of earthquakes and volcanic eruptions, the history of reversals of Earth's magnetic field, and the age and duration of a wide variety of other geological events and processes.