Editing Dysprosium (section)

===Isotopes===
{{main|Isotopes of dysprosium}}
Naturally occurring dysprosium is composed of seven [[isotope]]s: <sup>156</sup>Dy, <sup>158</sup>Dy, <sup>160</sup>Dy, <sup>161</sup>Dy, <sup>162</sup>Dy, <sup>163</sup>Dy, and <sup>164</sup>Dy. These are all considered stable, although only the last two are theoretically stable: the others can theoretically undergo alpha decay. Of the naturally occurring isotopes, <sup>164</sup>Dy is the most [[natural abundance|abundant]] at 28%, followed by <sup>162</sup>Dy at 26%. The least abundant is <sup>156</sup>Dy at 0.06%.{{NUBASE2016|ref}} Dysprosium is the heaviest element to have isotopes that are predicted to be stable rather than [[observationally stable]] isotopes that are predicted to be radioactive.

Twenty-nine [[radioisotopes]] have been synthesized, ranging in atomic mass from 138 to 173. The most stable of these is <sup>154</sup>Dy, with a [[half-life]] of approximately 3{{e|6}}&nbsp;years, followed by <sup>159</sup>Dy with a half-life of 144.4&nbsp;days. The least stable is <sup>138</sup>Dy, with a half-life of 200&nbsp;ms. As a general rule, isotopes that are lighter than the stable isotopes tend to decay primarily by β<sup>+</sup> decay, while those that are heavier tend to decay by [[Beta decay#β− decay|β<sup>−</sup> decay]]. However, <sup>154</sup>Dy decays primarily by alpha decay, and <sup>152</sup>Dy and <sup>159</sup>Dy decay primarily by [[electron capture]].{{NUBASE2016|name}} Dysprosium also has at least 11 [[metastable isomer]]s, ranging in atomic mass from 140 to 165. The most stable of these is <sup>165m</sup>Dy, which has a half-life of 1.257&nbsp;minutes. <sup>149</sup>Dy has two metastable isomers, the second of which, <sup>149m2</sup>Dy, has a half-life of 28&nbsp;ns.{{NUBASE2016|name}}