History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c27.s1.43

c27.s1.43

**Extraction of Zinc:**—Rub calamine with turmeric, the chebulic myrobalans, resin, the salts, soot, borax, and one-fourth its weight of *Semicarpus anacardium*, and the acid juices. Smear the inside of a tubular crucible with the above mixture and dry it in the sun and close its mouth with another inverted over it, and apply heat; when the flame issuing from the molten calamine changes from blue to white, the crucible is caught hold of by means of a pair of tongs and its mouth held downwards and it is thrown on the ground, care being taken not to break its tubular end. The essence possessing the lustre of tin, which is dropped, is collected for use. 157-161