The pre-feasibility study for the Filo del Sol project outlines a processing route based on heap leaching with copper solvent extraction and electrowinning, supported by extensive metallurgical testwork completed through 2018.
Report context
This NI 43-101 technical report was prepared for Filo Mining Corp. with an effective date of 13 January 2019. The report presents the results of a pre-feasibility study for the Filo del Sol project, a copper-gold-silver deposit located on the border between Chile and Argentina. The processing and metallurgical sections are documented in Chapter 13 (Mineral Processing and Metallurgical Testing) and Chapter 17 (Recovery Methods) of the original report.
Processing route
Process design overview
The proposed recovery methods described in the pre-feasibility study comprise a heap leaching operation followed by copper solvent extraction and electrowinning to produce copper cathode. The process description is provided in Section 17.1 and 17.2 of the report, with design criteria presented in Section 17.3.
Metallurgical testwork programs
Metallurgical testing was conducted in multiple phases. Phase IV testwork was completed by SGS Minerals (Lakefield) in 2018 and is documented in Section 13.2. Section 13.3 presents the results of the 2018 metallurgical program, including testwork outcomes for gold, silver, and copper recovery. Section 13.4 discusses alternative leaching processes that were evaluated but not selected for the base case design. Section 13.5 provides a preliminary evaluation of potential process improvements. Section 13.6 details miscellaneous test programs that were completed to support process design assumptions.
Metal recovery estimates
Metal recovery estimates are presented in Section 13.7 of the report. These estimates were derived from the metallurgical testwork programs and form the basis for process design performance assumptions in the pre-feasibility study.
Key reported parameters
| Parameter | Value | Basis |
|---|---|---|
| Processing method | Heap leaching with SX-EW | Proposed design (Section 17.1, 17.2) |
| Primary metal products | Copper cathode | Proposed design |
| Metallurgical testwork | Phase IV completed by SGS Minerals (Lakefield), 2018 | Historical testwork (Section 13.2) |
| Alternative processes evaluated | Yes – documented in Section 13.4 | Testwork comparison |
| Process improvements evaluated | Yes – preliminary evaluation in Section 13.5 | Testwork assessment |
| Miscellaneous test programs | Yes – documented in Section 13.6 | Historical testwork |
| Metal recovery estimates | Provided in Section 13.7 | Derived from testwork |
| Design criteria | Presented in Section 17.3 | Proposed design basis |
Project website: https://en.wikipedia.org/wiki/Filo_del_Sol
Technical qualifications
The metallurgical testwork programs were conducted by SGS Minerals (Lakefield) in 2018, with results documented in Section 13.2 and 13.3. The recovery methods described in Chapter 17 represent the proposed design for the pre-feasibility study. Alternative leaching processes and potential process improvements were evaluated but do not necessarily show final design selections. The miscellaneous test programs in Section 13.6 provide supplementary data supporting the metallurgical assumptions. Design criteria in Section 17.3 are based on the testwork outcomes and engineering analysis completed for the pre-feasibility study.
Source: NI 43-101 Technical Report, Pre-feasibility Study for the Filo del Sol Project, effective 13 January 2019, Sections 13 and 17.
