The Technological and Chronological Implication of 14C Concentrations in Carbon Samples Extracted from Mongolian Cast Iron Artifacts

Abstract

Cast iron objects recovered primarily in eastern Mongolia, spanning the Xiongnu through the Early Historic periods (ca. 3rd BC–AD 17th century), were examined for their radiocarbon (14C) concentration and microstructure. Most of the samples examined were found to have originated from charcoal-based smelting with a few exceptions that were made using a mineral coal-based technique. A comparison of 14C dates with dates derived from artifact typology allowed the charcoal-smelted objects to be classified into two groups, based on whether the radiometric and typological periodization are in agreement or not. In addition, those with differing 14C and typological dates can be divided into two subgroups with and without evidence for a melt treatment applied after original casting. These conflicting dating results are confusing and would seem to provoke skepticism about the use of 14C measurements for dating iron artifacts. We demonstrate however that 14C analysis, when combined with metallographic examination and other lines of chronological evidence, can clarify the history of a given iron object and its multiple users, often separated in time by more than a millennium.

Medieval long-wall construction on the Mongolian Steppe during the eleventh to thirteenth centuries AD

“…While the ceramics we recovered during the surveys are often dated to the Liao period (907-1125), they may well be from slightly later periods. Efforts to refine the ceramic typology using comparative techniques, as well as absolute dating of contexts associated with such ceramics in other parts of Mongolia, are underway (Makino 2007: 32-37 & 71;Shiraishi & Tsogtbaatar 2009;Park et al 2019a).…”

“…Efforts to refine the ceramic typology using comparative techniques, as well as absolute dating of contexts associated with such ceramics in other parts of Mongolia, are underway (Makino 2007: 32–37 & 71; Shiraishi & Tsogtbaatar 2009; Park et al . 2019a).…”

Novel Micro‐Scale Steel‐Making from Molten Cast Iron Practised in Medieval Nomadic Communities of East Mongolia

“…Evidence was found from radiocarbon analysis that cast‐iron fragments of widely varying chronological contexts were in fact collected and reused in later periods as inputs for this steel‐making process (Park et al . ). This aspect is also noted in the chemical composition of the objects examined, which, according to the data in Table , may be classified into two groups based on the presence of silicon.…”

“…It is important to note, however, that the level of these elements in the specimens, whether originating from charcoal‐ or coal‐based smelting, was much lower than that observed in coal‐smelted cast‐iron alloys (Rostoker and Bronson , Park and Reichert , Park et al . ) and that evidently was a result of the steel‐making treatment itself.…”