Cerro de Pasco Resources Advances Metallurgical Test Program for Quiulacocha Tailings
MONTRÉAL, June 09, 2026 – Cerro de Pasco Resources Inc. (TSXV: CDPR | OTCQX: CDPMF | BVL: CDPR | FRA: N8HP) has provided an update on its integrated metallurgical test program for the Quiulacocha Tailings Reprocessing Project in central Peru. Results from over 110 tests across multiple laboratories support a two-concentrate flowsheet, each concentrate containing silver, and demonstrate strong metallurgical responsiveness of Phase 1 tailings samples to conventional and emerging flotation technologies.
Key Highlights of the Test Program
The conceptual flowsheet generates two concentrate streams: a high-grade pyrite concentrate and a base metal concentrate, both bearing silver. Pyrite constitutes over 50% of the tailings drilled in 2024, and the company is evaluating the pyrite concentrate as an alternative sulphur source for industries such as phosphate fertilizers and chemical reagents in critical-metal processing.
In mini-pilot testing, over 92.5% of total sulphides and approximately 94% of silver (both lattice-bound and discrete) were recovered into a bulk concentrate alongside base-metal sulphides. The final tailings are targeted to contain low residual sulphur, potentially reducing acid-generation potential, which aligns with the company's remediation strategy.
Ongoing Optimization and Exploration
Bench and pilot-scale programs continue to refine the flowsheet and produce indicative concentrate specifications for technical studies and discussions with potential strategic offtake and investment partners. Mineralogical studies have also highlighted opportunities to concentrate gallium and indium, leading to targeted exploratory test-work on the silicate fraction for gallium recovery and on base metals and pyrite concentrate for indium recovery. This work remains at an early, conceptual stage.
Executive Commentary
Steven Zadka, Executive Chairman, commented: “This program has moved us from promising bench-scale results to a continuous mini-pilot test — an important step in evaluating a project of this scale. The results show strong recovery of silver and sulphides into a single bulk sulphide concentrate. A high portion of the silver is recovered with the sulphides rather than lost to tails, and our program is designed to investigate silver recovery through downstream processing of the pyrite concentrate. The pyrite dominance of these tailings is the reason we are pursuing a two-concentrate flowsheet: the pyrite stream has potential value as a sulphur-bearing feedstock in a market where conventional supply is tightening. Significant work remains — separation into a cleaner pyrite concentrate, roasting and calcine studies, and offtake discussions — but this material must ultimately be addressed, and we intend to be the ones to address it.”
Conceptual Metallurgical Flowsheet
The company continues to advance the project with further optimization work underway, aiming to deliver a robust flowsheet that maximizes recovery of valuable metals while minimizing environmental impact.
