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Isotopes of hafnium

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Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionJul 9, 2026
Entity authorityQ466147
Source-derived summary

Natural hafnium (72Hf) consists of five observationally stable isotopes (176Hf, 177Hf, 178Hf, 179Hf, and 180Hf) and one very long-lived radioisotope, 174Hf, with a half-life of 3.8×1016 years. The next most stable radioisotope is 182Hf with a half-life of 8.90 million years, an extinct radionuclide used in hafnium–tungsten dating to study the chronology of planetary differentiation.

Other isotopes have been synthesized running from 153Hf to 192Hf, but none of the 33 others has a half-life over 1.87 years, and most have half-lives under five minutes. There are also at least 41 nuclear isomers, the most stable of which is 178m2Hf with a half-life of 31 years. All isotopes of hafnium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.

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Begin with the source’s own compact description: “Isotopes of hafnium” is open-knowledge reference entry. The dossier treats that line as a proposition to test through Isotopes, hafnium and Open-knowledge, not as a finished interpretation.

Editorial reviewA dependable orientation record for establishing vocabulary, names and a first evidence trail. The current lead gives the account dated anchors—1016—that can be checked directly. The selected authority fields contribute no independent date. For this dossier, Isotopes, hafnium and Open-knowledge is the immediate research focus.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Jul 9, 2026. The linked authority identifier is Q466147. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1016.

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This entry incorporates text from Isotopes of hafnium” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.