The power of reflectance spectroscopy as an analytical tool for mineralogical studies has been known since the first half of the 20th century. However, it took several decades until this technology was widely adopted by the mineral exploration community as an operational tool, either in the laboratory or in the field. As a result, the identification of minerals associated with ore deposits using reflectance spectra has become one of the major applications of the technology in recent years. This paper summarizes some of the studies developed at the Institute of Geosciences, University of Campinas (Brazil), in which reflectance spectroscopy in the visible, near-infrared and shortwave infrared played a key role in unveiling subtle mineralogical information related to different types/styles of mineral deposits. The applications to be reviewed include the characterization of the hydrothermal alteration mineralogy in a gold-bearing epithermal deposit in Patagonia, Argentina, in a porphyry copper deposit in Chile, and in pegmatites of the Borborema Pegmatitic Province in northeastern Brazil.