The Magistral deposit is a calc-alkaline, copper-molybdenum, porphyry deposit with a well developed envelope of copper-(molybdenum) mineralized skarn (Ristorcelli et al., 2008).
There are three types of mineralization at the Project:
• Skarn: The skarn mineralization is of highest grade, forming a hundred-metre scale rim within the country rocks around the porphyries. Garnet (grossular at proximal and andradite at distal alterations), epidote, chlorite, hematite, magnetite, quartz and inosilicate minerals (pyroxene and amphibole) form the skarn gangue mineralogical assemblage. Centimetre-scale mineralized veinlets and massive patches of sulphide (chalcopyrite, pyrrhotite, pyrite, and minor molybdenite) crosscut the skarn gangue assemblage.
• Mixed zone: It consists of a metre-scale interlayering between the skarn and the porphyry style mineralization. It is possibly formed by the combination of exoskarn, endoskarn, and also intrusive fingers (porphyry), making a complex and variable sort of mineralization that combines mineralogical and grade characteristics of skarn and porphyry mineralization.
• Porphyry: The porphyry mineralization is of lowest grade and is formed by several quartz, chalcopyrite, and molybdenite veinlets (“D”, “B”, and “A”-type veinlets), which constitute a final stockwork framework that crosscuts the intrusive porphyry. The skarn mineralization seems to be preferentially elongated and anisotropic parallel to the st ........
