During the structural restoration of an Early-Chola era Shiva temple in the Sivagangai district of Tamil Nadu, conservationists discovered a concealed stone chamber beneath the main sanctum. Inside the vault, workers recovered five massive mercury-gilded copper plates containing inscriptions that detail royal land grants made by King Parantaka I to local Vedic scholars and temple artisans.
The Archaeological Survey of India (ASI) stated that the mercury-gilding technique used on these plates is exceptionally rare for the period, indicating a high level of metallurgical sophistication. The inscriptions provide new data on the 10th-century administrative systems and the specific agricultural taxes used to maintain the temple's daily rituals and seasonal festivals.