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Gold mineralization in the newly discovered Bhukia deposit in northwestern India is hosted in Proterozoic metamorphosed volcano-sedimentary rocks of the Aravalli-Delhi Belt. Three generations of tourmaline occurring in different textural settings are recognized in the host rocks of the deposit. Fine-grained texturally early tourmalines (Tur-I) precipitated during the gold-sulfide mineralization stage. They are dravitic in composition and occur parallel to the S₁ tectonic foliation as fine-grained crystals in tourmaline-albite layers within quartz-albite rock and as scattered grains in calc-silicate rocks. Coarse-grained texturally later schorls (Tur-II) are also restricted to calc-silicate and quartz-albite rocks and characterized by sector zoning. Late-stage type III tourmaline (Tur-III), also of schorl composition, replaces Tur-II along fractures and margins. They are interpreted to have formed during a phase of ore remobilization. All …