New isotopic fingerprinting of carnelian beads discovered at an archaeological site in Eritrea has confirmed their origin in the Indus Valley. The study, published in Antiquity, dates these artifacts to approximately 1000 BCE, providing definitive evidence of direct maritime trade links between the Horn of Africa and the Indian subcontinent during the early Iron Age.
By analyzing the strontium and lead isotope ratios within the beads, researchers were able to match them to specific quarries in Gujarat. This finding suggests that the "spice and incense" routes of the Red Sea were far more integrated with the Indian Ocean trade networks than previously thought, predating the formal Indo-Roman trade era by several centuries.