High-purity quartz (HPQ) is a critical raw material for strategic emerging industries such as semiconductors and photovoltaics, yet the supply chain for high-grade HPQ remains vulnerable. The North Himalayan belt hosts the world"s most extensive Cenozoic leucogranite belt, considered highly prospective for hosting high-quality white-granite-type HPQ deposits. However, systematic mineralogical studies and purification validation have been lacking. This study investigates quartz from the Malashan two-mica granite within this belt, aiming to characterize its impurity distribution, purification limits, and resource potential through integrated mineralogical analysis and systematic processing experiments. Methodology included mineralogical and fluid inclusion analysis using polarized light microscopy, scanning electron microscopy (SEM), and Raman spectroscopy. A comprehensive purification process—comprising crushing, flotation, calcination, water quenching, mixed acid leaching, and chlorination roasting—was applied, with ICP-MS used to quantify 15 key impurity elements before and after purification. Results indicate that: (1) Malashan quartz exhibits favorable inherent quality, with low fluid inclusion abundance dominated by readily removable secondary inclusions; (2) After processing, quartz purity increased from 99.8969% to 99.9942% (4N4 grade). Flotation and acid leaching effectively removed associated mineral inclusions such as feldspar and mica, while chlorination roasting specifically reduced volatile lattice-bound impurities such as Li and Na; (3) The principal residual impurities in the final product were Al (43.34 ppm), Ti (8.03 ppm), and Li (1.69 ppm), occurring as isomorphous substitutions within the quartz lattice and resistant to conventional removal. This study demonstrates that quartz from the Malashan two-mica granite possesses the mineralogical attributes necessary for white-granite-type HPQ formation. Furthermore, highly fractionated, low-fluid-exsolution leucogranites in the North Himalayan belt represent promising targets for large-scale, high-quality HPQ resources..