All of this work is being guided by Nadia M. Caira, P. Geo., who joined Candente Gold in June of 2012 in the role of Independent Qualified Person for the El Oro Project. Final assays and interpretations will be applied to an upcoming 2013 amendment to the NI 43-101 technical report. The following are key parameters for the new interpretation.
Regional structure: The structural framework of the district is dominated by WNW/E-W and NE/ENE trending, down-to-the-north extensional/transtensional faults. The principal mineralized vein-faults trend NNW-SSE, with slight variations in strike that apparently create increased dilation. The wider vein segments, such as the major San Rafael Vein, trend 150 degrees whereas 160 degrees -170 degrees trending veins are narrower. In addition, NNE/N-S and ENE/E-W trending veins have been recently identified in a GeoEye-1 imagery interpretation. It is this trend, recently acquired from historic data that correlates well with higher grade mineralization.
The major veins have been crosscut and down-thrown by post-mineral extensional faults providing potential for blind mineralized veins to occur at deeper structural levels in the hanging-walls of these structures.
Several broad circular features have been recognized in a recent imagery analysis that probably represents eroded stratovolcanoes or calderas, some with associated domal features that reflect subvolcanic domes, intrusive stocks and/or volcanic necks. Pre-, syn- and post mineral sub-volcanic andesite sills, dykes and intrusions are common-place throughout the district. The NNW-SSE trending quartz-filled vein faults lie along an anticlinal domal feature related to a specific stage of andesitic emplacement. Other intrusive phases spatially and possibly genetically-related to gold mineralization include: pre-mineral andesite porphyry sills; and syn-mineral quartz-eye rhyolite porphyry and syenite porphyry dykes.
Vein mineralogy: The veins show multiple pulses of crustification (banding) and replacement textures including: early chalcedonic quartz; bladed quartz after calcite; bladed calcite; dolomite followed by colloform banded quartz - adularia; and late drusy cavity-fill with evidence for multiple brecciation and overprinting events. Sulphides historically reported include: native gold, native silver, electrum (Au-Ag amalgam), and Ag sulfo-salts (Sb-Pb) including pyrargyrite (AgSbS3) and auriferous pyrite. Silver sulphides, galena, sphalerite and traces of chalcopyrite appear at deeper elevations within the system. Alteration of flanking wall rocks includes inner quartz-adularia-Kspar and outer chlorite-carbonate(s). Buddingtonite and kutnahorite were also identified in the upper unconformity-related gold target below the Somera Tuff. Kutnahorite is simply a Mn-rich carbonate between siderite and dolomite. Manganese is ubiquitous in epithermal veins. Buddingtonite, however, is an ammonium-feldspar that is exceptional and characterizes major epithermal systems like Fresnillo.
Vein types and silver to gold ratios: The veins in the districts can be separated into oxidized veins (developed by influx of meteoric waters along post mineral faults) and sulphide veins. The known oxidized veins include: San Rafael; Verde; Descubridora and San Patricio. San Rafael and Verde vein zones are reportedly up to 70 meters in width and are transverse to the NNW vein swarm trend and are of moderate grade, while some of the much narrower, early and steep sulphide-rich hanging wall veins are higher in gold grades.
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