Based on the text, which statement best explains how the findings at Pattanam challenge previous historical conclusions?
Many Hellenistic-era glass artifacts discovered in South Asia were made using plant-ash fluxes rather than mineral natron, a flux characteristic of Mediterranean manufacturing. Because Mediterranean workshops in Egypt and the Levant relied almost exclusively on natron, some historians concluded that South Asian communities maintained little to no exchange with Mediterranean glassmakers during the third century BCE. However, recent excavations at Pattanam in southwestern India uncovered glassworking crucibles containing residue of natron-rich glass slag alongside native quartz sands. Rather than importing finished Western glass vessels, South Asian artisans appear to have imported raw natron glass ingots, which they then melted and blended with local materials to produce regional wares.