Holmium-160

Main isotopes of holmium

iso NA half-life DM DE (MeV) DP 163Ho syn 4570 y ε 0.003 163Dy 164Ho syn 29 min ε 0.987 164Dy 165Ho 100% is stable with 98 neutrons 166Ho syn 26.763 h β− 1.855 166Er 167Ho syn 3.1 h β− 1.007 167Er
Standard atomic weight (Ar)	7002164930330000000♠164.93033(2)

Natural holmium (₆₇Ho) contains one stable isotope, ¹⁶⁵Ho. A number of synthetic radioactive isotopes are known, the most stable one is ¹⁶³Ho, with a half-life of 4,570 years. All other radioisotopes have half-lives not greater than 1.117 days in their ground states (although the metastable ^166mHo has a half-life of about 1,200 years), and most have half-lives under 3 hours.

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