Excavations at the ancient mining site of Zawar in Rajasthan have unearthed a complex of zinc distillation retorts dating back to the 4th century BCE. According to the Journal of Indian Metallurgy and Heritage, these findings predate previously known industrial-scale zinc production in the region by several centuries, highlighting the sophisticated metallurgical expertise of ancient Indian scientists.
The discovery includes clay retorts, furnace structures, and residue of high-purity zinc, which requires a complex "downward distillation" process. This technique, described in later Sanskrit texts like the Rasaratna Samuccaya, appears to have been perfected much earlier than historians previously estimated. The scale of the site indicates that the zinc was likely produced for the creation of high-quality brass alloys used in trade and ritual objects.
Archaeologists emphasize that this find confirms India as a global leader in ancient chemistry and material science. The ability to isolate zinc, a metal with a low boiling point that usually escapes as vapor, represents a pinnacle of ancient engineering that was not replicated in Europe until the late 18th century.