Geological and Cultural Heritage of Lithic Artefacts Unearthed from Fort Kochi, Southern India

Fort Kochi, an island in central Kerala (southern India), is the site of the earliest European settlement in Asia with a unique history of successive possession by the Portuguese, the Dutch, and the British from 1503 to 1947. This study investigates the geological and cultural linkage of a collection of finely crafted lithic artefacts, including pillar and beam-like structures, recently unearthed from Fort Kochi. We used archaeological, architectural, and geological constraints in this study. Typological examinations revealed a Portuguese connection with the prominent Gothic architectural style. Historical maps indicate that the artefacts likely belong to a demolished Portuguese Church that once existed on the beachside of Fort Kochi. Petrographical and whole-rock geochemistry data from representative samples of the artefacts confirmed the use of granite and gabbro in erecting the structures. We analyzed the geochemical data of artefact samples to determine their original geological source. By comparing the data with published information on granites and gabbros in different tectonic blocks in southern India, we found compositional and petrogenetic similarities between the artefact rock samples and the Munnar granites and Theni-Rajapalayam gabbros. As a result, we have identified these sites as the likely geological provenance for the artefact rocks. The historical records of the Portuguese trade routes through these ghat areas may provide clues about how the rocks were transported to Fort Kochi. This study highlights the potential for Fort Kochi to be recognized as a colonial Renaissance heritage site.