Evolution of an ancient VMS ore-forming system recorded by pyrite and sphalerite mineral texture, trace elements, and sulfur isotope: A case study from the Huangtupo Cu-Zn (-Au) deposit, Eastern Tianshan, NW China

•Mineral texture and elemental analysis reveal multi-stage mineralization.•The chemical composition (especially As, Co, Ni, Pb, Se of pyrite and Fe, Cu, Mn, and Sb of sphalerite) and textures of pyrite and sphalerite reflect the evolution of physicochemical conditions during mineralization.•Elemental mapping and sulfur isotope analysis reveal the introduction of a short-term gold-rich fluid that re-enriches gold by coupled dissolution and reprecipitation.