Pyrite and Pyrrhotite

Abstract

Pyrite and pyrrhotite are the only minerals other than native sulphur used in the manufacture of sulphuric acid. Pyrite is known to occur separately in Amjhore area of Bihar and as associated mineral in the complex base metal sulphides of copper, lead and zinc and also in the Kolar gold deposits. Pyrrhotite is known to occur in association with pyrite in Saladipura area, Rajasthan and also in the other sulphide deposits. Both pyrite and pyrrhotite were usually beneficiated by gravity methods when they are liberated at a coarse size, or by flotation when the grain size was fine. Depending upon the size of liberation either heavy media separation alone or followed by Jigging/Tabling were employed for the lumpy and coarse grained sulphides. Pyrite samples from Amjhore and Kolar areas were tested in NML. Amjhore Pyrites were lumpy in nature and hence heavy media separation and jigging were employed while tabling was employed to recover the sulphides from the fines. Pyrite samples from kolar and Nilgiris were beneficiated by Tabling and flotation methods. Pyrite Pyrrhotites from Saladipura were beneficiated by flotation only.