Petrology of Garimanipenta (copper Mineralisation Area), Nellore District, Andhra Pradesh, South India- a Case Study

The present study indicate that the copper mineralization in the area is of the nature of scattered sporadic occurrences of narrow lenticular and impersistent stringers and veins of copper-ore in vein-quartz and pegmatite traversing the amphibolite and garnetiferous mica schist country rock. The old workings for copper ore at Garimanipenta, which had a checkered history since early times, are based on oxidized zones containing malachite, azurite and some chalcocite in pegmatite rock and quartz veins. The previous reports of high copper content of the lodes obtained from the shallow old workings relate to oxidized supergene material, mainly quartz and pegmatite rock, coated profusely with malachite. The association of supergene malachite and other oxidized copper minerals in pegmatite rock in the area is also a very unfavorable indication, as the pegmatite is generally the root-zone of metalliferous hydrothermal veins.