Archaeological digs at the site of Pundravardhana in North Bengal have uncovered an extensive industrial precinct from the Gupta Era. The zone consists of specialized drainage systems, circular brick vats, and chemical residue traps designed for large-scale silk dyeing.
Chemical analysis of the soil indicates the use of indigenous plant-based mordants and minerals that produced the vibrant crimson and indigo hues famous in the ancient world. This discovery confirms the region's status as a global leader in textile technology and high-value exports during India's classical age.