The aims of this study were to observe invisible gold, including that present in fine minerals, using back scattered electron (BSE) imagery, and to recover gold using microwave-nitric acid leaching experiments of powdered ore samples, including of invisible gold. As it is difficult to observe gold-bearing, fine minerals using a polarized microscope due to its resolution, BSE images and energy dispersive spectrometer (EDS) analyses were used in this study to easily identify brighter, fine minerals containing gold. As a microwave-nitric acid leaching test was applied to the powdered ore samples, arsenopyrite and pyrite were completely decomposed in a very short period of time. Both the nitric-acid leaching solution and insoluble residue were easily filtrated with three filter papers. In the nitric-acid leaching solution, Au was not dissolved at all, whereas Ag, Cu, and Zn were completely leached. When analyzing the insoluble residue, the first filter paper containing fine particles, as well as the second and third filtrated samples were used in the lead-fire assay respectively. All of the gold particles were effectively recovered from the samples during this experiment.