Chronological attribution of ancient iron-smelting furnaces (SE altai, mountains of South Siberia) based on analysis of archaeological charcoal

Abstract

The article examines specific features of using charcoal as a material for the chronological attribution of iron-smelting furnaces in the mountainous southeastern Russian Altai. Archaeological charcoal from bloomery hearts of ancient nomad has a high potential not only for radiocarbon dating, but also for tree ring analysis. The use of radiocarbon analysis meets some difficulties associated, first of all, with the accuracy of dates, including those obtained by AMS technique. Another fundamental reason for the erroneous oldening of these monuments is the old wood effect, when the number of missing peripheral rings remains unknown. Tree ring analysis of charcoal in this context has great potential. With its annual resolution it can solve the problem of precise dating, and combining a large number of individual ring series can also minimize the old wood effect. This paper presents new radiocarbon dates for charcoal extracted from iron slag, including the results of Bayesian analysis, as well as 377 year-long tree ring chronology, being one of the longest in the world based on archaeological charcoal. Analysis of these data together with all available radiocarbon dates for box-shaped iron smelting furnaces in the Kuektanar location (highlands of Russian Altai) evidence for the functioning of Kosh-Agach type furnaces in the ancient Turkic period (late 5th − 10th centuries AD), which is also supported by few associated archaeological finds.