Iron technology in medieval Kerala: archaeometallurgical studies on iron artefacts from Triprangode

Abstract

Iron was a new entrant and a must in weaponry in the 2nd and 1st millennium BCE. There is every possibility of iron being used for generations, and deposited or hidden it for use in the times of need or even as a part of religious activities. Dating iron has been mostly based on the associated finds, and iron has been repeatedly melted, shaped and reused. Differentiating the iron in use at present from that in earlier times has been a challenge, and requires the dating of artefacts. Chemical objects characterization is contextual-specific. Three iron objects recovered from a cave near Triprangode, Kerala, India was studied using various analytical techniques to understand the metallurgical characteristics such as microstructure, phases, inclusions and production technology. The artefact was also dated using accelerator mass spectroscopy (AMS). The three artefacts included two swords and a tripod, which were reported to belong to the 1st millennium BCE based on associated pottery finds and typological comparison. Optical microscopy and scanning electron microscopy techniques were mployed for microstructure analysis. X-ray fluorescence analysis was used to identify the elements present in the samples. X-ray diffraction and energy dispersive X-ray spectroscopy analyses were performed to identify the phases present in the samples. AMS radiocarbon dating was carried out to determine the age of the artefacts. A combination of these techniques helped identify the iron-making process.