Ormaque consists of gently dipping, extensional quartz-tourmaline-carbonate veins flanking reverse faults. The veins are surrounded by alteration halos, which contain tourmaline, carbonate, and pyrite; these are locally overprinted by late albite and pyrite. Native gold and Au-Ag-Te-Bi–bearing polymetallic minerals occur as inclusions and fracture-fill in pyrite, tourmaline, and carbonate, and as disseminated grains along grain boundaries. Ormaque is dominated by extensional veins and differs from other Val-d’Or deposits, which are either dominated by fault-fill veins (e.g., Triangle, Plug No. 4, and Mine No. 3) or comprise both fault-fill and extensional veins in more equal proportions. The Ormaque deposit is hosted in a porphyritic dioritic intrusion, the C porpyry, emplaced in intermediate volcaniclastic rocks of the Val-d’Or Formation. Three vein generations, V1, V2, and V3, are present at the Ormaque deposit. Two alteration events are associated with the V2 quartz-tourmaline-carbonate veins: (1) an early tourmaline-carbonate-pyrite alteration, and (2) a later albite-pyrite alteration.

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