Researchers at the Archaeological Survey of India, in collaboration with international geochronologists, have successfully applied a novel Titanium-Diffusion dating methodology to stone toolkits found in the Middle Son Valley. The results push back the chronology of the 'Intermediate Acheulean' phase to approximately 185,000 years ago, providing new data for the timeline of hominin dispersal across the Indian subcontinent during the Middle Pleistocene.
This new technique measures the microscopic diffusion of titanium ions into the crystalline structure of chert and quartzite tools after they were flaked by early humans. This breakthrough allows for a more precise relative dating of artifacts in riverine environments where traditional radiocarbon dating is ineffective. The findings suggest that early South Asian hominins possessed more advanced lithic technologies much earlier than previously hypothesized, bridging the gap between African and East Asian evolutionary records.