COPPER GIANT ACHIEVES UP TO 92% COPPER AND 97% MOLYBDENUM RECOVERIES IN LATEST METALLURGICAL TESTWORK AT MOCOA

Executive Summary

• Bench‑scale rougher flotation tests on the Mocoa copper‑molybdenum project returned copper recoveries up to 92 % and molybdenum recoveries up to 97 %, exceeding the company’s current resource model assumptions of 90 % Cu and 75 % Mo.
• Mineralogical work confirmed chalcopyrite as the dominant copper mineral and molybdenite as the sole molybdenum carrier, with negligible deleterious minerals, supporting a clean‑flotation concentrate outlook.
• The results establish a baseline for a next‑generation metallurgical program that will feed into a forthcoming Preliminary Economic Assessment (PEA).

Key Details

• Test Program Scope
• Conducted by SGS del Perú (ISO/IEC 17025 accredited) on a single ≈130 kg composite built from drill holes MD‑043, MD‑044, MD‑045 (depths 262–928 m).

• Tests included grind size optimization, pH optimization (9–11), and reagent suite variations (PAX collector, Matcol 715 collector, Aero 7261A depressant, diesel & MIBC frothers).

• Recovery Results

• Base case (pH 11, standard reagents): Cu 88.85 %, Mo 95.22 %
• Best copper recovery: Test 01 (additional PAX) – Cu 92.24 %, Mo 97.39 %

• Best molybdenum recovery: Test 02 (iron depressant) – Cu 89.77 %, Mo 96.72 %

• Grind Size Optimization

• P80 150 µm identified as optimal; at this grind: Cu 88.05 % (4.31 % Cu grade), Mo 96.24 % (7 094 ppm Mo).

• Coarser grind (210 µm) reduced recoveries to ~81 % Cu and 93 % Mo.

• pH Optimization

• Robust performance across pH 9–11; pH 10 gave the best overall Cu‑Mo balance (Cu 88.43 %, Mo 95.55 %).

• pH 11 selected for reagent optimization due to highest Cu recovery.

• Reagent Optimization

• Adding PAX collector boosted Cu to 92.24 % and Mo to 97.39 % (Test 01).

• Iron depressant (Aero 7261A) yielded Cu ≈ 90‑92 % with Mo ≈ 95‑97 % (Tests 02 & 03).

• Mineralogy

• XRD: quartz ~50 wt %, muscovite/illite ~18 wt %, K‑feldspar ~17 wt %; sulfides – pyrite 3.5 wt %, chalcopyrite 1.2 wt %, molybdenite 0.15 wt %.

• TIMA‑X/PMA imaging confirmed 97 % of molybdenite present as free grains; chalcopyrite primarily disseminated and veinlet‑hosted.

• Implications

• High recoveries validate the use of a conventional flotation flowsheet for Mocoa and support more optimistic economic assumptions in the upcoming PEA.

• Absence of deleterious minerals (e.g., enargite, tetrahedrite) suggests potential for clean concentrate marketing.

• Next Steps

• Develop an integrated metallurgical circuit (beyond single‑variable tests).
• Explore re‑grind and advanced reagent schemes to further lift recoveries.
• Conduct concentrate quality testing and marketability studies ahead of the PEA.

Notable Quotes

“These first metallurgical tests… have already exceeded the recovery assumptions… The results give us strong confidence in a conventional flowsheet and will inform future economic studies.” – Ian Harris, President & CEO

Materiality Assessment: Material – Positive (the test results materially improve project economics and are forward‑looking for a PEA).