Announcement • Jul 11
Andina Copper Reports Initial Discovery Drilling Results At Piuquenes North
Andina Copper Corporation reported diamond drill assay results from drillholes PIU12 and PIU13 at the newly generated and previously undrilled Piuquenes North target in San Juan, Argentina. Drilling was designed to test a large, discrete MT (magneto-telluric) geophysical target delineated in the Company’s 2026 geophysical survey program. Assay results for drillhole PIU13 confirms the discovery of a new porphyry copper-gold system at Piuquenes North: 468m @ 0.50% Cu, 0.30 g/t Au, 3.04 g/t Ag from 700m; Including 164m at 0.70% Cu, 0.44 g/t Au, 4.19 g/t Ag from 924m. Mineralization in PIU13 is hosted within a strongly developed multiphase porphyry system which was intersected between 664m and 1,168m downhole. An intense quartz vein stockwork is developed within a potassic altered early mineral porphyry phase. Chalcopyrite and bornite occur in porphyry M, A and B quartz veins and disseminations, consistent with a high temperature potassic porphyry core. Gold is a significant co-product, with lesser silver. Hole PIU12 collared approximately 600m east northeast of PIU13, intersected short intervals of mineralization within a pre mineral porphyry and is interpreted to be on the periphery of the mineralized system. PIU12 and PIU13 have only tested a small part of the targeted MT geophysical anomaly, which measures approximately 800m by 700m and trends toward the north-northeast. The anomaly remains to be tested in all directions. Piuquenes is now confirmed to host multiple porphyry centres, comprising the Piuquenes North discovery, and the previously reported Piuquenes Central and Piuquenes East systems, all of which lie immediately adjacent (to the north) of Aldebaran Resources Inc. (ALDE.TSXV) Altar copper-gold porphyry project. PIU13 was drilled at an azimuth of 050 degrees and a dip of minus 70 degrees to a final depth of 1,235m. The hole collared in andesitic volcanic host rocks and, from approximately 664m downhole, intersected a broad, mineralized multiphase porphyry system extending continuously to approximately 1,168m. The intrusive complex comprises pre mineral, early mineral and intermineral porphyry phases, all affected by potassic alteration (secondary potassium feldspar, biotite and magnetite), locally overprinted by sericite and chlorite alteration. Copper-gold mineralization occurs throughout all porphyry phases as chalcopyrite and bornite hosted in M, A and B type quartz veins and as disseminations within the potassic altered intrusive. The highest-grade interval is associated with the early mineral porphyry between approximately 914m and 1,045m downhole, while the underlying intermineral porphyry continues to host consistent copper and gold mineralization at lower grades. The low-resistivity MT anomaly targeted by PIU12 and PIU13 has been demonstrated to correspond with a broad, mineralized multiphase copper-gold porphyry system. PIU13 returned 468m grading 0.50% Cu, 0.30 g/t Au and 3.04 g/t Ag from 700m. The porphyry system remains open to the north, north-northeast and at depth. PIU12 was drilled at 255 degrees azimuth and minus 70 degrees inclination to a final depth of 987.35m. The hole intersected andesitic volcanic host rocks for the first 832m, with dikes and apophyses of the pre mineral porphyry throughout, before entering the main body of the pre mineral porphyry, which shows moderate potassic alteration overprinted by sericite and chlorite and carries M, A and B type quartz veinlets with pyrite, chalcopyrite and trace bornite. PIU12 confirms that the porphyry system extends laterally at Piuquenes North. Assay results returned 14m @ 0.38% Cu, 0.12 g/t Au and 1.81 g/t Ag from 864m, including 8m @ 0.46% Cu, 0.15 g/t Au and 2.35 g/t Ag. The modest tenor and pre mineral porphyry host are interpreted to represent the periphery of the mineralized system, supporting the interpreted upside immediately to the north. The final depth of 987.35m reported here reflects the verified drilling contractor and geological log records and supersedes the 992.60m stated in the Company’s 28 May 2026 News Release. The Piuquenes District Work completed since 2024 has established Piuquenes as a cluster of copper-gold porphyry centres located immediately south of the Altar porphyry cluster (Aldebaran Resources Inc. (ALDE.TSXV)), within the Miocene porphyry belt of San Juan Province, Argentina, approximately 190km west of the city of San Juan. The Project now comprises three recognized porphyry systems: the newly discovered Piuquenes North system reported in this News Release, together with the previously identified Piuquenes East and Piuquenes Central copper-gold porphyry systems. References to the Piuquenes East and Piuquenes Central targets are based on the Company's previous public disclosure, supported by geological mapping, geochemical sampling and geophysical surveys. Other significant porphyry copper deposits and projects in the region include El Pachón (Glencore), located approximately 30km to the south, the Los Pelambres copper mine (60% Antofagasta plc) in Chile immediately across the international border, and Los Azules (McEwen Copper), approximately 50km to the northeast. Mineralization on adjacent or nearby properties is not necessarily indicative of mineralization at Piuquenes. The deep low resistivity MT anomaly at Piuquenes North, which measures approximately 800m by 700m and extends to depth, was the primary geophysical target tested by PIU12 and PIU13. The assay results from PIU13 confirm that copper and gold bearing sulphide mineralization is present within the targeted volume. The two holes tested only a portion of the anomaly, which remains largely untested at depth and along strike. The Company is planning to conduct measurements of resistivity and chargeability on representative core to refine the geophysical interpretation. The Company will integrate final assay results with updated geological logging into a refined three-dimensional geological model for Piuquenes North. This integrated dataset will be used to finalize the design of a follow-up drill programme targeting the down-dip and along-strike extensions of the newly identified porphyry system, with priority given to testing the north-northeast continuation and the untested depth extent of the MT anomaly. Drill holes PIU12 and PIU13 were collared using a PQ drill bit and subsequently reduced to HQ and then NQ diameter as drilling progressed. Drill core was extracted from the core barrels by the drilling contractor under the supervision of Andina Copper personnel and placed in labelled core boxes with appropriate depth markers.
