This paper explores the geological relationships, mineralogical and geochemical characteristics, and quantitative elemental mass balance constraints of the hydrothermal alteration zones within the uraniferous Surda copper deposit in the Singhbhum Shear Zone in eastern India, which is affiliated with an iron oxide-copper-gold system. Five distinct alteration zones are identified: a proximal potassic (biotitization) zone containing magnetite-apatite; a central chloritization zone containing copper, uranium, gold and magnetite; distal silicification (quartz) and albitization zones; and a transitional chlorite-sericitization zone. Evidence suggests these zones originated from mafic precursors linked to a subduction zone. Magnetite mineralization shows both magmatic (delta O-18 + 2.0 to +4.8 parts per thousand) and hydrothermal (delta O-18 + 0.4 to +0.6 parts per thousand) signatures. Hydrothermal magnetite-apatite formed at temperatures of 440 to 550 degrees C, with continued crystallization at lower temperatures (280 to 360 degrees C) concurrent with copper sulfide and uranium precipitation from an Fe-rich, isotopically heavy fluid (delta S-34 + 4.55 to +9.66 parts per thousand). Major elements (Ca, Na, Mg) and some minor and rare earth elements decrease from weakly altered mafic rocks to late alteration zones, reflecting the breakdown of Ca-bearing hornblende, biotite and plagioclase. Potassium decreases from early to late alteration zones due to mineral transformations. Mass-balanced geochemical data align with hydrothermal alteration mineral assemblages, indicating processes such as mineral dissolution, element absorption and sulfide behaviour. Overall, the study highlights the complex hydrothermal alteration processes shaping the Surda copper deposit and provides insights into ore formation mechanisms.