RETRACTED: Genesis of sulfide hosted invisible gold mineralization within the Vempalle dolostone of Korivipalle area, Cuddapah Supergroup, southern India.

Abstract

In this work, the Vempalle dolostone hosted auriferous sulfides are studied to understand the genesis of the invisible gold mineralization in and around Korivipalle area, Cuddapah Basin, southern India. A detailed petrographic examination, scanning electron microscopic study and microprobe data, reveals the presence of various sulfide phases i.e. pyrite, chalcopyrite, and galena. Textural characteristics of pyrites indicate two types of pyrite generations i.e. sedimentary pyrite (Py1) and hydrothermal pyrite (Py2). The Co/ Ni values of Py1 & Py2 varying from 0.1 to 0.82 and 2.29 to 12.98 support the sedimentary and hydrothermal origins of pyrites, respectively. The Laser Ablation Inductively Coupled Mass Spectrometric study on both generations of pyrite suggests the occurrence of invisible gold mineralization within the Vempalle dolostone in solid solution as well as nano-inclusions. The precipitation of pyrite grains along the oolitic grain boundary suggests the prevailing redox environment. The reducing environment is further aided by the stromatolitic association within the dolostone. The present work is the first report on the sulfide hosted invisible gold mineralization within the Vempalle dolostone of Korivipalle area of Cuddapah Supergroup in Southern India.