Naturally occurring zinc (30Zn) is composed of the 5 stable isotopes64Zn, 66Zn, 67Zn, 68Zn, and 70Zn with 64Zn being the most abundant (48.6% natural abundance). Twenty-eight radioisotopes have been characterised with the most stable being 65Zn with a half-life of 244.26 days, and then 72Zn with a half-life of 46.5 hours. All of the remaining radioactive isotopes have half-lives that are less than 14 hours and the majority of these have half-lives that are less than 1 second. This element also has 10 meta states.
Zinc has been proposed as a "salting" material for nuclear weapons. A jacket of isotopically enriched64Zn, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope 65Zn with a half-life of 244 days and produce approximately 1.115 MeV[4] of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several years. Such a weapon is not known to have ever been built, tested, or used.[5]
^( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
^# – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
^ ab# – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
^Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3): 030003. doi:10.1088/1674-1137/abddaf.
^Nies, L.; Canete, L.; Dao, D. D.; Giraud, S.; Kankainen, A.; Lunney, D.; Nowacki, F.; Bastin, B.; Stryjczyk, M.; Ascher, P.; Blaum, K.; Cakirli, R. B.; Eronen, T.; Fischer, P.; Flayol, M.; Girard Alcindor, V.; Herlert, A.; Jokinen, A.; Khanam, A.; Köster, U.; Lange, D.; Moore, I. D.; Müller, M.; Mougeot, M.; Nesterenko, D. A.; Penttilä, H.; Petrone, C.; Pohjalainen, I.; de Roubin, A.; Rubchenya, V.; Schweiger, Ch.; Schweikhard, L.; Vilen, M.; Äystö, J. (30 November 2023). "Further Evidence for Shape Coexistence in Zn 79 m near Doubly Magic Ni 78". Physical Review Letters. 131 (22). arXiv:2310.16915. doi:10.1103/PhysRevLett.131.222503.
^ abShimizu, Y.; Kubo, T.; Sumikama, T.; Fukuda, N.; Takeda, H.; Suzuki, H.; Ahn, D. S.; Inabe, N.; Kusaka, K.; Ohtake, M.; Yanagisawa, Y.; Yoshida, K.; Ichikawa, Y.; Isobe, T.; Otsu, H.; Sato, H.; Sonoda, T.; Murai, D.; Iwasa, N.; Imai, N.; Hirayama, Y.; Jeong, S. C.; Kimura, S.; Miyatake, H.; Mukai, M.; Kim, D. G.; Kim, E.; Yagi, A. (8 April 2024). "Production of new neutron-rich isotopes near the N = 60 isotones Ge 92 and As 93 by in-flight fission of a 345 MeV/nucleon U 238 beam". Physical Review C. 109 (4). doi:10.1103/PhysRevC.109.044313.