The Igor Project, located in the Callanquitas Gold-Silver Deposit in La Libertad Region, Perú, is a proposed heap leach operation designed to process gold and silver mineralization from underground mining.
Report context
This technical report and pre-feasibility study (PFS) for the Igor Project was prepared for PPX Mining Corp. and dated January 18, 2019. The report documents mineral processing and metallurgical testing conducted between 2014 and 2018, along with a proposed processing plant design, at the Callanquitas deposit in the La Libertad Region, Perú.
Processing route
Historical testwork (2014–2015)
Initial metallurgical testwork conducted during 2014 and 2015 included column-leach tests, agitated tank tests, and bottle-roll tests. A Bond work index test was performed in 2014 by OMI. Gravity separation tests were also completed in this period. A microscope mineralogical study conducted in 2015 provided both qualitative and quantitative mineralogical characteristics of the material. The qualitative study identified mineralogical characteristics, while the quantitative study determined mineralogical composition, with comments provided on the microscopic mineralogy results.
2017 testwork
In 2017, two composites designated M1 and M2 were prepared for further testwork. Head analyses were performed on both composites. Characterization of grades by size fraction included grain size analysis. Bottle-roll (quick cyanidation) tests were conducted. Column-leach tests were carried out at METTS in 2017. Agglomeration strength tests were also performed during this period.
2018 testwork at METTS
Testwork conducted in 2018 at METTS included sample preparation for column tests, chemical and other characterization of the samples, and column tests. Granulometric analysis was performed on both the head and leached spent material. A discussion of 2018 blended column-leach tests was included in the report.
Toll processing of bulk samples (2016–2018)
Toll processing of bulk samples was conducted from 2016 through 2018.
Proposed process plant design
The report presents a proposed process plant design based on heap leaching with Merrill-Crowe recovery. The proposed processing route includes:
Crushing: A three-stage crushing circuit comprising primary, secondary, and tertiary crushing stages. A vibratory grizzly feeds the primary crusher. A secondary screen and secondary crusher follow, then a tertiary screen and tertiary crusher.
Crushed-ore stockpile and conditioning: Crushed ore is stockpiled and conditioned prior to agglomeration.
Agglomeration and transfer to leach pad: The agglomerator is designed for crushed ore agglomeration. Agglomerated material undergoes curing before being transferred to the leach pad.
Heap leaching: The leach pad configuration and operation are designed for heap leaching. Sand separation is included in the circuit. Pregnant solution ponds and an emergency pond are part of the solution handling system, with solution handling pumps.
Gold and silver recovery (Merrill-Crowe) and bullion production: The pregnant solutions are clarified, then processed through a Merrill-Crowe circuit. Circuit equipment includes compressed air supply. Cyanide destruction is performed. A precipitate wash system and mercury recovery system are included in the design.
Process reagents: The proposed reagent scheme includes sodium cyanide (NaCN), lime, cement, anti-scaling agent, zinc powder, lead nitrate, sodium metabisulfite (SMBS), copper sulfate, anti-fouling agent, diatomaceous earth (DE), and melting fluxes.
Water supply and management: Fresh water supply, process water and heap leaching water, and water for road irrigation are part of the water management design.
Key reported parameters
| Parameter | Units | Basis |
|---|---|---|
| Bond work index test | , | 2014 OMI testwork |
| Column-leach tests | , | 2014–2015, 2017, 2018 METTS testwork |
| Bottle-roll (quick cyanidation) tests | , | 2014–2015, 2017 testwork |
| Agglomeration strength tests | , | 2017 testwork |
| Grain size analysis | , | 2017 testwork |
| Granulometric analysis (head and spent material) | , | 2018 testwork |
| Head analyses (M1 and M2 composites) | , | 2017 testwork |
Technical qualifications
This report is a pre-feasibility study and does not constitute a feasibility study. The processing design and parameters are based on metallurgical testwork conducted between 2014 and 2018, and represent proposed design criteria. Historical testwork from 2014–2015, 2017 testwork, 2018 testwork, and toll processing of bulk samples from 2016–2018 are each reported separately with their respective methodologies and results. The report does not include operating data from a full-scale processing facility at this project.
*Source: Technical Report and PFS, Igor Project, PPX Mining Corp., January 18, 2019, Sections 13.0 (Mineral Processing and Metallurgical Testing) and 17.0 (Recovery Methods)*
