NGEx Minerals Ltd. has completed initial metallurgical testwork on representative core samples from its Lunahuasi copper-gold-silver project in San Juan Province, Argentina. The test program achieved final clean copper concentrate grades ranging from 23.4% to 39.4% copper and 9.5 g/t to 43.7 g/t gold, with copper recoveries spanning 92.0% to 94.2% across the project’s Saturn, Mars, and Jupiter zones.

The initial work evaluated a two-phase flowsheet comprising sequential flotation and concentrate treatment alternatives. The flotation stage relied on a simple sequential flowsheet using rougher stages without cleaning stages, aided by the deposit’s coarse-grained nature and simple mineralogy.

Because enargite is the primary copper mineral, the initial raw concentrates contained arsenic above conventional smelter limits. NGEx tested several secondary treatment options to remove the arsenic into a stable form. The company found that Dundee Sustainable Technologies' GlassLock process removed over 95% of the arsenic from the copper concentrate, achieving a mass reduction of 25% to 30% while recording no losses of copper, gold, or silver. Alternative pathways, including producing on-site copper cathode and doré, also yielded positive results.

“These initial metallurgical results are highly encouraging and an important first step in understanding the processing characteristics of the mineralization at Lunahuasi. Although additional variability, optimization and scale-up work will be required, these initial results achieve strong recoveries of copper, gold, and silver and provide a solid technical foundation for further metallurgical studies at Lunahuasi.”

— Wojtek Wodzicki, President and CEO

The metallurgical samples were drawn from the Phase 4 drill program, which concluded in April 2026 with 27,318 metres completed across 32 diamond drill holes. Building on this work, the Mining Authority of San Juan Province approved the Environmental Impact Statement in March 2026 to develop an exploration adit at the site, which will support underground evaluation.

NGEx plans future testwork to incorporate material from high-grade gold veins and porphyry-style mineralization as it evaluates trade-off studies and optimal processing strategies.

NGEx plans future testwork to incorporate material from high-grade gold veins and porphyry-style mineralization as it evaluates trade-off studies and optimal processing strategies.

Read the full announcement: NGEx Minerals Reports Positive Preliminary Metallurgical Results from Lunahuasi