Economic and Engineering Evaluation of Granitoid Rocks in the Western Himalayas, Northern Pakistan

This study presents an integrated petrographic, mineralogical, and geomechanical evaluation of granitoid rocks, including granodiorite, granite, pegmatite, and aplite, from the Kohistan and Karakoram “Batholiths” exposed in the Nomal and Hunza regions of the Western Himalayas, Northern Pakistan. Granodiorites from the Nomal area exhibit hypidiomorphic granular textures and are primarily composed of quartz, plagioclase, orthoclase, perthite, and microcline, with accessory minerals including biotite, hornblende, zircon, and monazite. Granites display a comparable mineral assemblage, with additional features such as deformation fabrics and metamorphic overprints, suggesting tectonothermal reworking. The presence of xenoliths, thermal metamorphism, and mylonitization within these granitoids supports a complex postemplacement history. Trace amounts of malachite and visible native gold point to hydrothermal or possibly syngenetic mineralization processes. Geomechanical analyses indicate that Nomal granite possesses high uniaxial compressive strength (UCS), low porosity, high specific gravity, and low water absorption, making it suitable as a durable dimension stone for structural applications. In contrast, the granodiorite exhibits relatively higher porosity and lower UCS, which limits its suitability for load-bearing applications but makes it more suitable for nonstructural uses. The enrichment of accessory minerals such as zircon, monazite, titanite, and apatite in the granodiorite highlights its potential for “rare earth elements (REEs)” exploration. Overall, the results demonstrate the dual economic importance of the studied granitoids as both sources of strategic mineral resources and high-quality construction materials. Further, multidisciplinary investigations are recommended to comprehensively evaluate the mineralization potential and guide future development of quarry sites in the region.