ODM2 Variable Name Controlled Vocabulary ODM2 Working Group A vocabulary for describing the name of Variables. Lead-208 Stable isotope of lead. The term stable isotope has a meaning similar to stable nuclide, but is preferably used when speaking of nuclides of a specific element. Hence, the plural form stable isotopes usually refers to isotopes of the same element. The relative abundance of such stable isotopes can be measured experimentally (isotope analysis), yielding an isotope ratio that can be used as a research tool. Wikipedia https://en.wikipedia.org/wiki/Isotopes_of_lead https://en.wikipedia.org/wiki/Stable_isotope_ratio Added to support Critical Zone Observatory (CZO) data use cases.