Abstract <p>Three ore stages have been identified for the gold-copper-porphyry mineralization of the Despen ore field, associated with granites of the Bice-Serlig massif of the Early–Middle Cambrian Tannuola complex. The I-st gold-bornite-chalcopyrite-quartz ore stage is represented by chalcopyrite, bornite, pyrite, galena, molybdenite, cassiterite, gold, and electrum; the II-nd gold telluride–palladium-sulfide–quartz ore stage–by gold, electrum, keithconnite Pd₂₀Te₇, temagamite Pd₃HgTe₃, telluropalladinite Pd₉Te₄, kotulskite Pd(Te,Bi), mertiite Pd₈(Sb_2.5As_0.5)₃, Au and Ag tellurides selenides; and the III-rd gold-telluride-sulfide-quartz ore stage–by gold, electrum, acanthite, Ag and Bi tellurides, native Bi, alloclasite, cobaltite, barite and ankerite. Fluid inclusion data in quartz (microthermometry, Raman spectroscopy) showed that the I-st ore stage minerals were formed at <i>P</i> ~ 0.4–0.5 kbar from CO₂H₂O chloride (Na) fluid with a salinity of 18.2–34.8&#xa0;wt % in NaCl-eq. at 400–338°C; minerals of the II-nd ore stage–at <i>P</i> ~ 0.45–0.75 kbar from CO₂H₂O-chloride (Na) fluid with a salt concentration of 16.1–32.8 wt % in NaCl-eq. at 386–366°C, and those of the III-rd ore stage–from CO₂H₂O–chloride (Na-K) fluid with a salinity of 7.2–12.1 wt % NaCl-eq. at 286–190°C. Near-zero values of sulfur isotopic composition of the fluid (from +1.6 to +2.1‰) at different ore stages indicate the involvement of a homogeneous magmatic fluid of the copper–porphyry system. The values of the oxygen isotopic composition of the fluid show that the fluid was of magmatic origin during the I‑st and II-nd stages of the ore-forming process (from +5.7 to +6.8‰) and mixed with meteoric waters in the III-rd (from +0.8 to +1.8‰) stage.</p>