Exploring the Sierra Madre of Mexico for gold and base metals.
Porphyry copper and molybdenum
Stockworks, dissemination and breccias of chalcopyrite and molybdenite-rich mineralization are associated with a Paleocene granitic complex in the western part of the Property. Accessory tin, tungsten, bismuth, gold and silver also occur in this style of mineralization.
Porphyry systems are defined as large volumes (10 to more than 100 cubic kilometers) of hydrothermally altered rock centered on one or more intrusive rocktypes. Principal economic parts of porphyry systems typically take the form of an inverted cup or trough above their causative intrusions. Level plans of the economic portion of porphyry systems typically show radial mineral and metal zoning from (i) a silicic core, (ii) a potassic ore zone of quartz, potassium feldspar, magnetite, biotite, chalcopyrite, bornite and molybdenite with economic grades of copper, molybdenum and other metals, (iii) phyllic alteration dominated by pyrite, sericite and muscovite, and (iv) distal propylitic alteration with epidote and chlorite. Horizontal dimensions of the silicic through the phyllic zones range from a few hundred meters to 5 or 6 kilometers across. Vertical extent of the economic mineralization is usually less tham 1500 m.
Copper and molybdenum stockworks related to porphyritic intrusions at Picachos have not been explored with either geophysics or diamond drilling. Geochemical results mentioned below are from hand trenching and surface sampling.