0015-573X Radiocarbon measurements of iron girders from Aachen cathedral Hüls Christian Matthias author Christian-Albrechts-Universität zu Kiel 04v76ef78 Correspondence to: Christian Matthias Hüls mhuels@leibniz.uni-kiel.de 28 02 2025 Vol. 92 (2024) 2024 79 90 Copyright © 2025 2025 <div>Radiocarbon dating of ancient iron and steel has been successfully demonstrated over the past decades. Yet, interpretation of the results could get complicated in view of possible contamination with exogeneous carbon from a) old wood used to produce coal, b) flux additives such as calcites, and c) cutting tools used in sampling. The latter contamination can be minimized to below common measurement uncertainties.<br />Sample material from two iron girders of the Carolingian Palace Chapel as well as from two iron beams from the Gothic Annex of Aachen Cathedral became available for radiocarbon dating during renovation work. 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