Pathfnder elements and indicator minerals of Au from the Kubi Gold ore deposits in Ghana

Abstract

The Au mineralization in the Kubi Gold Mining Area in the Birimian of Ghana is associated with garnet (about 85 vol.%), magnetite, pyrrhotite, arsenopyrite, and sulfde minerals, as well as quartz with gold and calcite. These minerals and the included elements can act as indicator minerals or pathfnder elements. For the present work, we collected samples from drill holes at diferent depths, from the alluvial zone (0–45 m) to the ore zone (75–100 m). The distributions of minerals and elements in the rocks that act as indicator minerals and pathfnder elements in the concession area were investigated along the drill hole cross sections. X-ray difraction shows that the samples contain garnet, pyrite, periclase, and quartz as the main indicator minerals. By energy-dispersive X-ray spectroscopy, Fe, Mg, Al, S, O, Mn, Na, Cu, Si, and K are identifed as corresponding pathfnder elements. The results indicate that the Au mineralization in the Kubi Mine area correlates mostly with the occurrence of garnet, pyrite, goethite, and kaolinite in the host rocks, which show towards the surface increasingly hematitic and limonitic alteration in form of Fe(oxy-)hydroxides.