Iron 59 (Fe-59)
Iron has 28 known isotopes, with mass number between 45 to 42), 4 stable (Fe-54, Fe-56, Fe-57 and Fe-58) and 4 radioactive (Fe-52, Fe-56, Fe- 55, Fe-59 and Fe-60). Iron is present in the natural state only in stable form, the isotope Fe-56 being largely the majority (91.7%). The most stable of iron radioisotopes is Iron 60 (Fe-60) with a half life of 2.6 million years, followed by Fe-55 with 2.7 years, Fe-59 with 44.5 days And Fe-52 with 8.5 hours, all other isotopes having a half-life of less than 10 minutes. The lighter isotopes than the stable isotopes disintegrate mainly by positron (β +) emission in manganese isotopes and the heavier isotopes by β-emission in cobalt isotopes.Iron 59 (Fe-59) is a heavy iron radioisotope with a mass number of 59 and a half life of 44.5 days. This isotope emits beta particles and rays ranges, and is used as a tracer in the study of iron metabolism.