The Charaka Samhita, thought to have been written between 300 and 500 AD, mentions a metal which, when oxidized, produces pushpanjan, thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period. The smelting of metallic zinc here, however, appears to have begun around the 12th century AD. One estimate is that this location produced an estimated million tonnes of metallic zinc and zinc oxide from the 12th to 16th centuries. Another estimate gives a total production of 60,000 tonnes of metallic zinc over this period. The Rasaratna Samuccaya, written in approximately the 13th century AD, mentions two types of zinc-containing ores: one used for metal extraction and another used for medicinal purposes. COUNT 5
QSN1 Zinc oxide is believed to be mentioned in what ancient text? ANS1 The Charaka Samhita QSN2 Active zinc mines in India date back to what period? ANS2 Mauryan period QSN3 What process occurred around the 12th century? ANS3 smelting of metallic zinc QSN4 When was the Rasaratna Samuccaya written? ANS4 13th century AD, QSN5 What are the two uses of zinc ore mentioned in the Rasaratna Samuccaya? ANS5 metal extraction and another used for medicinal purposes