Mineralization within the Cerro San Pedro district fits within two general classes of deposit types: 1) intrusion-hosted stockwork and/or disseminated sulphides/oxides within the San Pedro porphyry, and 2) carbonate replacement deposits (CRD) containing oxides and manto-style sulphides within the adjacent limestone.
Typically, the replacement mineralization within the limestone at CSP has one of the following geometries:
• tabular shaped at the porphyry–limestone contact • tabular to elongate fault-controlled veins and breccias
• circular to ovate, shallow to steeply raking breccia pipes/stockwork alteration zones.
The mineralization at Cerro San Pedro has two principal forms: 1) gold and silver within iron oxide minerals, and 2) gold, silver, zinc, and lead (plus minor, locally occurring copper) within sulphides. Both styles of mineralization are hosted within a well-developed system of crosscutting fractures (stockwork) in the San Pedro porphyry and along faults and fractures that extend into the surrounding limestone country rock. In addition, secondary oxide-hosted gold and silver mineralization is present in the nearsurface parts of the Cerro San Pedro district. Here, surficial weathering and oxidation has removed zinc, lead and copper from pre-existing primary sulphide minerals. The majority of the current mineral resources and reserves are contained within the gold and silver bearing oxide portion of the Cerro San Pedro deposit. Although ........
