Recent restoration work on a historic Kalyani Chalukya temple in Telangana has led to the discovery of hidden subterranean water storage units located beneath the main mandapa. These ritual cisterns are uniquely lined with a bismuth-based alloy, a material choice that modern researchers believe was used for its natural antimicrobial properties to keep sacred water pure.
This discovery suggests that medieval Indian architects possessed sophisticated knowledge of metallurgy and hydro-hygiene. The temple authorities are working with heritage experts to preserve these metal-lined reservoirs, which represent a rare intersection of ancient religious practice and advanced material science.