Malaysian Journal of Geosciences (MJG)

The Magnetic Hinge deposits from Chirano Gold Mine lie within the Paleoproterozoic Birimian rocks of southwestern Ghana on the West Africa Craton. The Analytical Spectral Device (ASD) Terraspec Spectrometer is used to measure the composition and abundance of a variety of alteration minerals. The results obtained through the ASD on rock cores are plotted as strip logs plots, box plots and the creation of geological models using Leap Frog Geo. The different alterations identified using the ASD were sericite, chlorite, carbonate, amphibole, chlorite-amphibole, kaolinite and epidote. Cutoff grades lesser than 0.2 ppm were considered insignificant mineralization and hence were of no interest. The Magnetic Hinge boasts of carbonate, sericite, and sericite-chlorite alterations hosting good gold grades in rocks and this was observed from the results obtained. Moreover, Magnetic Hinge is a new project and reverse circulation was done to obtain information on the subsurface alterations, open pit mining may be done and as progress is made, diamond drilling can be done to obtain subsurface information for much deeper depth.