Geology
- Property Geology -
Mineralization
Exploration on the Haquira property has located both primary and secondary copper mineralization. The main focus of Antares Minerals Inc.’s 2005-2006 exploration program was the further delineation of the secondary copper mineralization original defined by Minera Phelps-Dodge del Peru S.A.C. To-date, the primary (hypogene) mineralization has not been fully tested.
Given the relative paucity of pyrite in the main system, most of the secondary mineralization is characterized by black copper oxides, principally tenorite and pitch limonite. Brochantite and chrysocolla are commonly associated with the oxidation of chalcocite. Chalcocite “blankets” are best formed in and proximal to structures. Given the high permeability, the structures are sites of repeated leaching/enrichment as manifested by the rare occurrence of cuprite and native copper.
The best mineralization is spatially associated with two stocks and associated dyke swarms located at the intersection of the thrust fault and north-northwest-striking structures; the mineralization has a strong structural control. Quartz- and sulphide-bearing stockwork typical of porphyry copper systems is recognized in these stocks and has penetrated the stratigraphic section, especially in proximal silicified hornfels. Sulphides also occur in structures and the arenites and quartzites host sulphide veinlets, probably as pre-existing fracture infill. Disseminated mineralization is common throughout the project area.
Primary (hypogene) mineralization consists of pyrite, chalcopyrite, and molybdenite with lesser amounts of bornite. Where the intrusive rocks are potassically altered, quartz veinlets host chalcopyrite-pyrite-molybdenite. Outward from these central zones, the sulphides are pyrite-chalcopyrite, and beyond a halo of pyrite-specularite.
|