Andina Copper Corp. (TSX-V:ANDC) (FSE:FIR) (OTCQB:PMMCF) reported a wide intercept of copper-gold-silver mineralization at Piuquenes East, significantly expanding the vertical extent of the mineralized envelope and confirming increasing gold grades and intensity of porphyry stockwork veining laterally and to depth.
Drill hole PIU09, only the third drilled at Piuquenes East, intersected a broad, continuous interval of copper–gold mineralization hosted within strongly veined, dioritic porphyry with intense sericitic alteration overprinting potassic, confirming the presence of a new vertically extensive gold-rich porphyry Cu–Au–Ag system within the Piuquenes-Altar cluster. Highlights include 126 m at 0.46% Cu, 0.53 g/t Au, 2.14 g/t Ag from 529 m, within 402 m at 0.25% Cu, 0.21 g/t Au, 1.19 g/t Ag from 253 m. Well developed A-type veins coincident with chalcopyrite ± bornite mineralization were observed, with higher gold grades and increasing intensity of A and B-type veining noted at depth, consistent with proximity to the porphyry core. Bornite-rich potassic alteration with higher gold grades may be preserved beneath the sericitic overprint.
Follow-up drilling is underway to evaluate the northern continuity of the Cu–Au mineralized porphyry system at Piuquenes East. A second rig has commenced drill testing of a strong, discrete geophysical anomaly (MT) at Piuquenes North, immediately adjacent to the Piuquenes Central deposit (refer 10 February 2026 News Release).
Follow-up drilling at Piuquenes East continues to expand porphyry copper-gold mineralization first intersected in hole PIU06 (208 m at 0.31% Cu, 0.13 g/t Au, 1.24 g/t Ag from 292 m including 98 m at 0.49% Cu, 0.16 g/t Au, 1.26 g/t Ag from 292 m (refer 30 April 2025 News Release). Drill hole PIU09 further extends the mineralized system, with mineralization commencing at approximately 517 m downhole and higher-grade Cu-Au-Ag mineralization beginning at 529 m. The deeper mineralized interval is hosted within crowded dioritic porphyry exhibiting well developed sericitic alteration overprinting potassic represented by intense chalcopyrite-bearing A > B veins. Veining intensity increases downhole, with moderate to strong quartz–sulphide stockwork development locally reaching 40–60 veinlets per metre. Hydrothermal magmatic breccias are developed along intrusive contacts laterally to the mineralized zone. Intense sericitic alteration overprinting potassic assemblages indicates the system underwent substantial telescoping, suggesting potential for a potassic gold-rich core at deeper levels.
Follow up hole PIU11 is designed to test the northern continuity of the Cu–Au-Ag mineralized porphyry system and evaluate the lateral and vertical extent of the mineralized corridor identified to date. The hole has been positioned to intersect a geophysical chargeability anomaly defined by Induced Polarization (IP) surveying and a coincident conductive feature identified in Magnetotelluric (MT) data. The spatial relationship between these geophysical features and the mineralized dioritic porphyry intersected in PIU06 and PIU09 represents a priority target within the evolving geological model at Piuquenes East. Importantly, PIU11 is oriented to test both hypothetical geometries of the mineralized dioritic porphyry body, allowing the Company to evaluate competing structural interpretations while maximizing the probability of intersecting the mineralized porphyry system at depth.
A second drill rig has commenced (PIU12) testing a strong, coherent, deep-seated, low-resistivity anomaly at Piuquenes North identified by the recently completed MT geophysical survey (refer 10 February 2026 News Release). The anomaly is characterized by its low-resistivity contrast, significant vertical extent commencing ~600 m below surface and extending well below the limits of current drilling beneath the known mineralized centres at Piuquenes East and Piuquenes Central. Integration of the MT data with existing IP datasets, drilling results, alteration mapping and structural interpretation has improved understanding of the spatial relationship between deeper conductive features and overlying porphyry-style mineralization. This relationship suggests that the currently defined Piuquenes East and Central mineralization may represent upper-level expressions related to a deeper source at Piuquenes North. The MT Anomaly will be tested by the PIU12 drill hole and PN02 (planned), designed to test this feature and its interpreted relationship to known mineralization.
These results demonstrate increasing gold grades and intensifying porphyry-style veining at depth within potassic-altered diorite porphyry, with the deeper mineralized interval remaining open and chalcopyrite-dominant with minor bornite, suggesting potential for continued strengthening of the system at depth. PIU11 represents a key step in assessing the scale potential of the Piuquenes East porphyry centre.
