Gold Mineralisation around Babaikundi Area in Singhbhum Group of Rocks, Ranchi District, Jharkhand

The volcano-Sedimentary assemblage of rocks belonging to the Singhbhum Group of Proterozoic age is exposed around Babaikundi, in Ranchi district of Jharkhand state. The east-West trending Tamar-Porapahar shear zone passes north of Babaikundi area. The Chotanagpur Granite Gneissic Complex (CGGC) is to the north of the area, while the rocks of the Dalma Volcanic Belt (DVB) are exposed towards the south. The rocks of the area have undergone polyphase deformation and subjected to metamorphism ranging from greenschist to lower amphibolite facies.

Gold mineralisation is of epigenetic type and is mainly confined to the lensoidal sheared quartz vein traversing the litho-Contacts of the quartz-Mica schist and amphibolite of the Singhbhum Group. The attitude of the mineralised quartz vein is in conformity with the regional schistosity trending ENE-WSW. At the footwall contact of the mineralised quartz vein extensive wall rock alteration halos are observed in the amphibolite unit in the fOrm of pervasive biotitisation, carbonatisation, sericitisation, chloritisation, sulphidisation and Silicification. Ore microscopic studies of the mineralised quartz vein reveal that the native gold is associated, at places, with pyrrhotite and sphalerite. Pyrite and chalcopyrite along with magnetite are also present within the mineralised quartz vein. The paper presents the salient details on the occurrence of primary gold mineralisation in Babaikundi area.