Andina Copper Corporation (TSX-V: ANDC | FSE: FIR | OTCQB: PMMCF) reported an outstanding drill intercept from hole CDH005 at its Cobrasco Project in Choco, Colombia. The hole was designed to test the southern extensions of the Cobrasco system to a depth of 700m, in a large step-out over an area of limited geological data and no prior drilling. Results confirm a large-scale southerly extension of copper-molybdenum-silver mineralization, demonstrating a large multi-phase porphyry system with newly observed intermediate intrusive phases consistently mineralized over broad intervals.
Drillhole CDH005 was collared from the same platform as holes CDH002, CDH003, and CDH004 and oriented due south to test the southern extensions. The hole tested approximately 600 m of lateral extent and 700m of vertical extent, terminating at a downhole depth of 934 m. Unlike earlier holes that intersected a multi-phase quartz-rich rhyolitic to dacitic subvolcanic dome complex, CDH005 is characterized by mineralized diorite to dacite-andesite porphyries, generally manifesting as magnetic intrusive sequences at surface transitioning to a magnetic low embayment at depth. The intermediate dacite-andesite units are intruded by several narrow quartz-rich felsic rhyolite subvolcanic intrusions.
The hole was collared within dark-colored diorite porphyry units and remained within this phase to approximately 170 m downhole before intersecting fine-grained dacite–andesite units. These subvolcanic porphyries exhibit visually significant chalcopyrite-dominant sulphide mineralization, accompanied by weak to moderate sericite alteration overprinting earlier potassic assemblages. The dacite–andesite units are intruded by thin apophyses of intermineral rhyolite porphyry and extend to approximately 630 m downhole, where the hole intersected a younger and lower-grade intermineral rhyolite porphyry that continues to end of hole at 934 m. The lower sections display epidote–chlorite alteration consistent with a propylitic assemblage, interpreted to represent the outer or lower zones of the Cobrasco hydrothermal system. The mineralization remains open to the south.
Drillhole CDH005 also differs from previous south-west trending drillholes with no phreatomagmatic breccias observed at depth. These breccias have exhibited very low-grade assays and have defined the SW limits to the Cobrasco Central mineralization system. The continuity of intrusive phases, alteration styles and sulphide mineralization throughout the drillhole is supported by wide intercepts of moderate to high grade copper mineralization, interpreted to be predominantly associated with the waning stages of potassic alteration transitioning into early sericitic alteration. Assay results support the interpretation of a large and long-lived mineralizing system extending south of the currently defined Cobrasco footprint.
Andina Copper's President and CEO Joseph van den Elsen commented: “Ongoing drilling at Cobrasco continues to demonstrate the large-scale and relatively shallow nature of Cobrasco Central, with results from hole CDH005 significantly extending the mineralized envelope to the south. With broad spaced holes having tested less than half the target area to-date, we see the potential for a globally significant copper deposit(s) at Cobrasco. To accelerate exploration and evaluation, a second drill will be mobilized to systematically explore and define the lateral extents of the Cu-Mo system and to add volume to the higher-grade copper shells intersected in drilling to date.”
The large, strongly coincident copper-molybdenum surface geochemical anomaly currently being tested by drilling extends approximately 2.5 km north–south and 900 m east–west. This soil anomaly is supported by limited rock chip geochemistry, geological mapping, and geophysical data collected to date. A systematic environmental baseline program has commenced across the project area and will be followed by detailed geological mapping and further surface sampling to support ongoing drill targeting. The Company’s Corporate Presentation is available at: Andina Copper Corporate Presentation. Interested parties can subscribe to the mailing list and follow social media channels: Mailing List | Andina Copper LinkedIn | Andina Copper X | Andina Copper Instagram.
