This report presents the definitive feasibility study processing design for the Kobada Gold Project in Mali, based on metallurgical testwork for oxide and sulphide ore treatment.
Report context
This technical report, titled “NI 43-101 Technical Report on Kobada Gold Project in Mali,” was prepared for African Gold Group, Inc. The effective date of the report is 29 September 2021, which serves as the cutoff date for all scientific and technical information included in the completed Kobada Gold Project Definitive Feasibility Study Report.
Processing route
Metallurgical testwork overview
Testwork was conducted on both oxide and sulphide ore types to define the process flowsheet and design criteria for the project.
Oxide testwork
Oxide ore metallurgical testwork was undertaken to assess comminution characteristics, head assays, mineralogy, and gold recovery options. Gravity recoverable gold testing and intensive cyanidation on gravity concentrate were performed. Bulk gravity and leach tests, along with gravity and CIL variability testwork, were completed. Additional testwork included oxygen uptake, viscosity, thickening and rheology studies, cyanide detoxification testing, and an arsenic balance assessment.
Sulphide testwork
Sulphide ore testwork was conducted with sample selection and testing to define summary results and design values. Phase 2 testwork was also performed to further characterise sulphide ore processing parameters.
Process plant design
The process plant design was developed from the flowsheet evaluation. For oxide ore, the comminution circuit was specified. For sulphide ore, a separate comminution circuit was defined. Gravity circuit simulation was undertaken, and carbon-in-leach (CIL) elution batch size was determined. Loaded carbon movement through the circuit was also incorporated into the design.
Process description
The processing route includes crushing and mill feed storage, milling, gravity recovery and concentrate leach, CIL gold recovery, cyanide detoxification, arsenic precipitation and tailings disposal, and tailings storage with return water. Ancillary unit operations comprise acid wash, elution, electrowinning, carbon reactivation, and the gold room. Reagent systems, diesel services, compressed air, and water services support the process plant operations.
Key reported parameters
| Parameter | Unit | Design / Actual / Testwork Basis |
|---|---|---|
| Oxides testwork | , | Testwork completed: comminution, head assays, mineralogy, gravity/leach, CIL variability, oxygen uptake, viscosity, thickening, cyanide detoxification, arsenic balance |
| Sulphides testwork | , | Testwork completed: sample selection, summary results and design values, Phase 2 testwork |
| Process flowsheet | , | Design: crushing, milling, gravity, CIL, elution, electrowinning, carbon reactivation, gold room, reagent and utility systems |
| Comminution (oxides) | , | Design basis from oxide testwork |
| Comminution (sulphides) | , | Design basis from sulphide testwork |
| Gravity circuit | , | Simulation conducted for design |
| CIL elution batch size | , | Determined for design |
| Loaded carbon movement | , | Included in design |
Project website: https://toubaniresources.com/project/
Technical qualifications
- This report is a NI 43-101 Technical Report with an effective date of 29 September 2021.
- The report specifically notes recommendations for additional metallurgical testwork for oxide ore.
- The process flowsheet and plant design are based on definitive feasibility study level information and may not show actual operational performance.
- No historical operating data from the project are presented in the report; all processing information is derived from testwork and design studies.
Source: NI 43-101 Technical Report on Kobada Gold Project in Mali, effective date 29 September 2021, sections 13 (Metallurgy) and 17 (Recovery Methods).
