The Global Phenomenon of Stone Spheres: New Findings from Zavidovići, Bosnia-Herzegovina and Implications for Prehistoric Technological Knowledge – Featuring the World’s Largest Stone Sphere

This study presents the results of a 25-year investigation into the global phenomenon of prehistoric stone spheres, with special focus on specimens from Zavidovići, Bosnia-Herzegovina—including the largest stone sphere ever recorded, discovered in the village of Podubravlje. Physical-chemical and petrographic analyses suggest artificial construction techniques, revealing potentially advanced prehistoric technological capabilities. The Podubravlje sphere, estimated at over 37 tons, surpasses the largest known Costa Rican spheres (up to 20 tons), positioning Bosnia as a significant archaeological reference point in the study of megalithic artifacts. Laboratory analysis identified the presence of calcium oxide (binding agent) and manganese (hardening agent) not found in surrounding natural stone, suggesting ancient knowledge of geopolymer technology.This research compares stone spheres across six continents, evaluates competing theories of natural versus artificial origin, and establishes a new framework for understanding this worldwide megalithic phenomenon. The findings have significant implications for reassessing prehistoric technological knowledge and cultural connections, challenging conventional archaeological narratives.