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The Remarkable Metrological History of Radiocarbon Dating [II]



Lloyd A. Currie


Radiocarbon dating would not have been possible if 14C had not had the wrong half-life -- a fact that delayed its discovery [1]. Following the discovery of this 5730 year radionuclide in laboratory experiments by Ruben and Kamen, it became clear to W.F. Libby that 14C should exist in nature, and that it could serve as a quantitative means for dating artifacts and events marking the history of civilization. The search for natural radiocarbon was a metrological challenge; the level in the living bioshpere [ca. 230 Bq/kg] lay far beyond the then current state of the measurement art. This article traces the metrological history of radiocarbon, from the initial breakthrough devised by Libby, to minor (evoluntionary) and major (revolutionary)advances that have brought ^14^C measurement from a crude, bulk [8 g carbon] dating tool, to a refined probe for dating tiny amounts of precious artifacts, and for molecular dating at the 10υg to 100υg level. The metrological advances led to opportunites and surprises, such as the non-monotonic dendrochronological calibration curve and the bomb effect, that spawned new multidisciplinary areas of application, ranging from cosmic ray physics to oceanography to the reconstruction of environmental history.
Journal of Research (NIST JRES) -
109 No. 2


accelerator mass spectrometry, apportionment of fossil and biomass carb, bomb 14C as a global tracer, dual isotopic authentication, metrological history, molecular dating, radiocarbon dating, SRM 1649a, Turin Shroud


Currie, L. (2004), The Remarkable Metrological History of Radiocarbon Dating [II], Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 21, 2024)


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Created August 1, 2004, Updated February 17, 2017