Characterization for Identification of Possible Beneficiation Strategies for Low-Grade PGE Ores from Mesoarchean Boula-Nuasahi Igneous Complex, Singhbhum Craton, India

Abstract

Comprehensive characterization studies are carried out to develop a suitable beneficiation process for treating low-grade platinum group elements (PGEs) ore from Mesoarchean Boula-Nuasahi Igneous Complex in southern part of Singhbhum Craton, eastern India. The PGE mineralization is magmatic and hydrothermal in origin and found in association with NNW-SSE-trending mafic-ultramafic igneous rocks in the tectonic brecciated zone toward the eastern part of the complex. The PGE-bearing minerals are very fine grained (< 1-50 mu) and exhibit heterogeneous distribution, with a total grade of 2.094 g/t. Chalcopyrite, pyrrhotite, pentlandite, pyrite, etc. are found as discriminate grains while the altered silicates (tremolite, riebeckite, enstatite, etc.) are the main gangue minerals present in this ore. The common PGE minerals, such as sperrylite, sudburyite, braggite, laurite, and testibiopalladite, are identified, and individual elemental distribution is analyzed by electron probe micro-analyzer mapping. Based on the studies, different flow schemes are proposed and discussed.