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Thursday, February 2, 2023

Monday, January 30, 2023

The regular zinc production by distillation started in India around 12th century AD and in China it is not earlier then 16th century AD. As early as the 12th century AD, India produced the metallic zinc by the sophisticated distillation process at Zawar in Rajasthan. This technology of zinc manufacture is also described in several Indian alchemical works of the mediaeval period including the 13th century Rasa Ratna Samuccaya. The word used in this document to describe the distillation process involved is tirakpatnayantra, which translated literally, means "distillation by descending". Various zinc-smelting processes were also described in the Sanskrit works of medicinal chemistry and alchemy, viz., Rasarnavam Rastantram (500-100 BC), Rasratnakar (2nd century AD) and Rasprakash Sudhakar (12th century AD). In China zinc was first reported in the 16th century by the excavation in Gui-Zhan region of Yun-han, but the new research by the Chinese scholars gives a clear indication that zinc smelting began in China in the Jiajung period (1552-1566 AD) of the Ming dynasty. In 17th century China exported zinc to Europe under the name of totamu or tutenag. Tutenag possibly has its origin in the word Tutthanagaa maening zinc in South Indian languages