Radioactive dating rates
Many of these radionuclides exist only in trace amounts in nature, including all cosmogenic nuclides.Secondary radionuclides will occur in proportion to their half-lives, so short-lived ones will be very rare.
This excess energy can be either emitted from the nucleus as gamma radiation, or create and emit from the nucleus a new particle (alpha particle or beta particle), or transfer this excess energy to one of its electrons, causing that electron to be ejected as a conversion electron.
Over 60 further radionuclides are detectable in nature, either as daughters of these, or through natural production on Earth by cosmic radiation.
More than 2400 radionuclides have half-lives less than 60 minutes.
This complex mixture of radionuclides with different chemistries and radioactivity makes handling nuclear waste and dealing with nuclear fallout particularly problematic.
Radionuclides are used in two major ways: either for their radiation alone (irradiation, nuclear batteries) or for the combination of chemical properties and their radiation (tracers, biopharmaceuticals).