Minerals and Metals in Ancient India v2.c44.s6.29

v2.c44.s6.29

A special feature in *Rasahṛdaya* text is the description of eighteen steps for purification of mercury in an apparatus like *dipikā yantra* (*RHR*, 1.1-8). It was stated that pure copper, amalgamated with mercury, when subjected to heat and distillation (*pātana*), produced pure mercury freed from lead and tin impurities (*RHR*, 1.8). Also described were various processes of ‘killing’ mercury with sulphur (*RHR*, 16.11-13). Orpiment or a mixture of sulphur and mica (*RHR*, 3.19-23). *Abhra* was probably a sulphide mineral with metallic lustre sometimes mistranslated as a ‘mica’.