The aphanitic muscovite discovered in late hydrothermal quartz veins in Daobulong gold deposits, Tibet, is characterized by aphanitic texture, massive structure, light kelly-grass kelly color, translucence, and greasy feeling. Due to the high similarity, it is often misclassified as serpentine or agalmatolite in the field. It is well-known that both serpentine and agalmatolite are generally rich in magnesium (Mg). It is demonstrated that this mineral belongs to a rare type of aphanitic muscovite, according to the physical and chemical properties of the mineral and the mineralogical analysis by X-ray diffraction (X-RD). oft-com:office:office" />