Unveiling historical salt production tradition in Aceh, Indonesia: Insight from Archaeometric analysis of ceramic artifacts from Samudra Pasai

This study investigates the historical salt-making practices in Aceh, Indonesia, through an archaeometric analysis of ceramic artifacts excavated from the Samudra Pasai archaeological sites. The research aims to unveil ancient production techniques by examining the elemental and mineral compositions of the pottery using XRF, XRD, and SEM-EDS, alongside microbial analyses of salt samples as a preliminary study. The findings suggest that certain pottery artifacts were directly linked to salt production, as evidenced by the presence of salt residues, including sodium chloride, particularly in fragments presumed to have functioned as scoops during the salt-boiling process. In addition, the comparison of locally produced boiled salt with solar-evaporated salt revealed significantly lower microbial content in the boiled salt, highlighting its hygienic advantages, likely due to prolonged heating during the production process. This mirrors traditional salt-making methods still practiced in coastal villages of Lancok Bayu and Matang Tunong, where salt is boiled from seawater—a practice that has likely continued for centuries. The historical significance of salt in the Samudra Pasai Sultanate is well-documented, with salt being a crucial commodity in regional trade. The discoveries enhance comprehension of the importance of salt manufacturing for the Pasai Sultanate's economy and its broader marine trading networks. The presence of contemporary pottery-making practices in the region further supports the hypothesis of a continuous cultural tradition, extending from the Samudra Pasai period to the present day. This research offers critical insights into the technological continuity and socio-economic importance of salt-making in Aceh, with broader implications for understanding Indonesia's trade and industry in the early Islamic era.