KOCHI: Gold cladding and gold plating are two different methods and a structure that has been cladded with gold can withstand weathering for 50 years, said Senthil Nadhan, the amalgamation expert who was deputed by businessman Vijay Mallya to assess the quality of work funded by him at Sabarimala in 1999.“The amalgamation work was conducted at Sannidhanam under the supervision of TDB engineers.

The work was executed by Chennai-based JNR Jewellery. I was brought to Sabarimala when the TDB complained of water leakage in the sanctum sanctorum after completion of the work. I removed the faulty teak wood and replaced the gold covering. After this, Mallya asked me to conduct a thorough inspection to avoid any issue in future,” he said.

Senthil said Mallya donated 30.3kg of 24 carat gold and 1,600kg of copper for the gold cladding. “The gold is flattened into thin foils of 2 microns each and 160 pieces of these foils weigh around 36 grams. The foils are kept in the pages of a book. Later, the foils are melted using mercury and spread over copper sheets to form a gold-mercury amalgam.

The sheets are then heated to vaporise the mercury, which will form a layer of pure gold. Many such layers are added to a sheet to improve quality. JNR Jewellery used seven to ten layers in sections that devotees could not reach out and touch. It was thicker on the roof and areas devotees can access,” said Senthil.