[Pramāṇa](https://indike.org/pramana/) › [Studies](https://indike.org/pramana/ins) › [Science, technology and education](https://indike.org/pramana/ins.science) › [History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray](https://indike.org/pramana/ins.science.ray-1956) › c37.s2 # History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c37.s2: Iron Sulphate History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c37.s2 - **Language:** English ### Iron Sulphate ### [c37.s2.1](https://indike.org/pramana/ins.science.ray-1956.c37.s2.1) "The green vitriol or copperas of commerce, which is known to the natives as \*kahi\* and \*hara kasis\*, is produced principally from the so-called alum shales, from which alum is prepared. As is the case also with alum, copperas is found sometimes as a natural exudation upon alum shales and other rocks, which include iron pyrites. ### [c37.s2.2](https://indike.org/pramana/ins.science.ray-1956.c37.s2.2) "This native copperas goes by several different names in India according to the nature of the other substances with which it is combined. ### [c37.s2.3](https://indike.org/pramana/ins.science.ray-1956.c37.s2.3) "In the year 1833, Mr. J. Stevenson published an analysis of native sulphate of iron obtained from Bihar, which was used at that time by the native dyers of Patna. ### [c37.s2.4](https://indike.org/pramana/ins.science.ray-1956.c37.s2.4) Analytical results:— ### [c37.s2.5](https://indike.org/pramana/ins.science.ray-1956.c37.s2.5) | Iron sulphate | .........39.0 per cent. | | Iron oxide | .........36.0 „ | | Magnesia | ........ 23.0 „ | | Loss | ...... .. 2.0 „ .” | ### [c37.s2.6](https://indike.org/pramana/ins.science.ray-1956.c37.s2.6) —Ball, loc. cit., p. 419. --- Source: [https://indike.org/pramana/ins.science.ray-1956.c37.s2](https://indike.org/pramana/ins.science.ray-1956.c37.s2) · Pramāṇa