Summary:
Deposit Types
In the Condor North area, gold and silver mineralization is located within the Condor breccia, dyke and dome complex as well as in the adjacent Chinapintza veins. The recently identified Nayumbi prospect located in the Condor South area, is consistent with low to intermediate sulphidation epithermal mineralization (Hedenquist et al., 1996).
Mineralization
The Condor breccia, dyke and dome complex hosts the Camp, Los Cuyes, Soledad, Enma and the Chinapintza vein deposits and the un-drilled Prometedor prospect.
Camp
The Camp deposit features gold and silver mineralization linked to a swarm of northwest-striking rhyolitedacite dykes, likely originating from a larger buried rhyolite intrusion. These dykes are concentrated at the contact between a volcanic/intrusive complex and a major granodiorite intrusion. The mineralized zone, dipping steeply at 85° to the northeast, extends over 500 m along strike and is 80 to 130 m wide.
Gold occurs within veins containing pyrite, marcasite, iron-rich sphalerite (marmatite), galena, ± chalcopyrite, pyrrhotite, quartz, and rhodochrosite gangue. Host rocks include altered granodiorites, breccias, flow-banded rhyolite, and phreatomagmatic breccia. The area is capped by 30 to 80 m of trachyte to rhyolitic welded tuff, with the Camp ridge bounded by the Camp Fault and Piedras Blancas Fault.
Anomalous surface copper mineralization and stockwork porphyry clasts with molybdenite in the nearby Los Cuyes diatreme suggest a deeper common mineralized porphyry underlying the Condor breccia, dyke, and dome complex.
Los Cuyes
Los Cuyes is hosted within an oval-shaped diatreme measuring 450 m northeast-southwest, 300 m northwest-southeast, and extending to at least 350 m in depth. This diatreme, resembling an inverted cone plunging approximately 50° to the southeast, consists of an outer shell of polymictic phreatomagmatic breccia and an internal fill of well-sorted rhyolitic lapilli tuffs, breccias, and volcanic sandstones. Amphibolite and quartz arenite fragments occur around its periphery, with dacite and rhyolite ring dykes intruding the steep margins.
Alteration within the diatreme is primarily sericite-illite, with localized carbonate and intense phyllic alteration at the margins, indicating focused hydrothermal fluid flow. Gold and silver mineralization occurs in veins containing pyrite, sphalerite, galena, chalcopyrite, and pyrrhotite. The entire diatreme exhibits a low background level of gold, primarily in disseminated pyrite and sphalerite. The highest gold values are found in veins of massive sphalerite, pyrite, and marcasite, with minor quartz, galena, and rhodochrosite, similar to the nearby Chinapintza veins.
Lithological contacts, such as dykes cutting through the diatreme and its outer breccia shell, favoured vein development. The mineralization and alteration at Los Cuyes post-date all local rock types, including blocks of the Hollín Formation, indicating that the mineralization is post-Early Cretaceous.
Soledad
The Soledad Zone features a 700-meter diameter oval-shaped rhyolite intrusion within the Zamora Batholith, surrounded by discontinuous pyritic breccias. It includes individual mineralized zones named Soledad, San Jose, Bonanza, and Guayas. Epithermal gold-silver mineralization at Soledad resembles that of the Camp deposit, with patchy matrix replacement by sulphides, grain-scale replacement of rhyolite feldspars by sphalerite and pyrite, and irregular sphalerite veinlets. Unique to Soledad are the pyritic hydrothermal matrix breccias at the upper margins of the intrusion at San Jose and Guayas.
The overall mineralization at Soledad is described as a north-south elongated wine glass-shaped body, tapering between 200 to 300 m below the surface and extending approximately 110 m northwest by 50?m northeast. Sphalerite transitions to pyrite as the dominant sulfide at around 100 m below the surface, leading to diminished gold and silver grades similar to Los Cuyes.
Enma
Gold and silver mineralization at Enma is hosted in a west-northwest-trending rhyolitic breccia that occurs at the contact between andesite lapilli tuffs and the Zamora batholith. The deposit has dimensions of 280 m east-northeast, is approximately 20-75 m wide, and has a vertical extent of 350 m. Alteration mineralogy is primarily chlorite with minor quartz-sericite ± alunite-kaolinite. Gold is associated with pyrite-sphaleritequartz and locally rhodochrosite veins. At depths greater than 200 m, gold-poor, pyrite-pyrrhotite ± chalcopyrite veins are more dominant.