Radiometric dating for dummies
Actually, it isn’t really a decay process in the normal sense of the word, like the decay of fruit.The daughter atoms are not lesser in quality than the parent atoms from which they were produced.
Geologists regularly use five parent isotopes to date rocks: uranium-238, uranium-235, potassium-40, rubidium-87, and samarium-147.
In some cases, the isotopes eject particles, primarily neutrons and protons.
(These are the moving particles measured by Geiger counters and the like.) The end result is a stable atom, but of a different chemical element (not carbon) because the atom now has a different number of protons and electrons.
So, for example, every carbon atom contains six protons and six electrons, but the number of neutrons in each nucleus can be six, seven, or even eight.
Therefore, carbon has three isotopes (variations), which are specified carbon-12, carbon-13, and carbon-14 (Figure 1).