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Shortwave infrared (SWIR) technology is characterized by high efficiency and convenience and is widely used in the mineral exploration of porphyry, epithermal, and skarn types. However, studies on the SWIR spectral features of porphyry tungsten deposits are still lacking. The Dahutang tungsten deposit has reached an ultra large scale, characterized by the porphyry type. Based on the SWIR spectral features of white mica and its petrographic, geochemical, and Raman spectral features, this paper discusses the use of shortwave infrared and Raman spectral features and major and trace element contents in white mica for exploration of the Shimensi mine in Dahutang. The results showed that the SWIR wavelength of the single-frequency Al-O-H absorption peak position (Pos2200) of white micas in ore-bearing intrusions were over 2209 nm; the Raman shift of aluminium atom bridge-bonds (Al, O (br)) were mainly located between 410 and 420 cm−1. The contents of Si, Fe, and Mg were relatively high; the contents of Al, Na, and K were low; and the variation of the Nb/Ta value reflected the magmatic evolution degree. The shift of Pos2200 of white mica showed a correlation with the Raman spectral features and contents of Si, Al, and other elements. This study shows that the SWIR spectral features of white mica were useful for further exploration of the Shimensi area in Dahutang and provided a potential tool for the exploration of porphyry tungsten deposits.

Raman spectroscopy is an important method to analyze and measure mineral composition and structure, which has the advantages of being non-destructive and rapid. This study considered garnet from the Jiama copper polymetallic deposit in Tibet to carry out micro-Raman spectrum and electron microprobe research to analyze the Raman spectrum characteristics of garnet with different components to reveal its indicative significance for garnet composition and skarn mineralization. The results showed that the Raman peaks T, X, A1, A2, and A3 shift toward lower wavenumber with the increase in andradite (And) content. The variations in T, X, and A2 are more obvious than those of A1 and A3. When And > 50%, the three Raman peaks (T, X, and A2) range are 173–174, 234–239, 513–525 cm−1; when And < 50%, they are 177–178, 240–244, 527–543 cm−1. The Raman peaks also shift with the cation radius and relative atomic mass. Different peaks moved in the low-frequency direction with the increase in the X2+ and Y3+ radius, and the X2+ atomic mass. The Raman spectrum can indicate the composition change in garnet. Raman spectrum analysis of garnet is of great significance for skarn zoning and prospecting.