The proposed processing route is a conventional zinc and lead–silver flotation circuit, based on metallurgical testwork that demonstrated amenability to froth flotation for zinc and lead–silver mineralization.
Report context
This technical report describes the Ayawilca Polymetallic Project as defined in the 2021 technical report. The project is a greenfields site located in a remote mountainous river valley area, 310 km by road north of Lima. The processing plant design is based on a lean, fit-for-purpose standard to cover the required duty for a projected 14-year mine life. The design accommodates nominal operation with a small degree of capacity flexibility for upsets and variability but has no consideration or allowance for any expansion. Site development earthworks are a major project consideration due to topography and potential geological hazards.
Processing route
Basis of circuit selection
The selection of a conventional zinc and lead–silver flotation processing circuit for Ayawilca was based on metallurgical testwork including locked cycle tests for zinc and open cycle tests for lead–silver. Metallurgical testwork showed that the Zinc Zone mineralized material is amenable to froth flotation, achieving commercial zinc concentrate grades and recoveries.
Proposed processing plant
Processing of the zinc–lead–silver mineralization will be through a conventional flowsheet comprising primary crushing, semi-autogenous grinding (SAG), secondary ball mill grinding, lead and silver flotation, zinc flotation, concentrate thickening and filtration. The concentrator plant will produce two concentrates: a zinc concentrate and a lead–silver concentrate.
The processing plant will consist of the following unit operations:
- Primary jaw crushing
- Crushed ore handling
- SAG milling
- Ball mill secondary grinding in a closed circuit with hydrocyclone classification
- Lead circuit, including rougher flotation, cleaner flotation
- Zinc circuit, including rougher flotation, regrind, cleaner flotation
- Concentrate dewatering (zinc and lead–silver concentrates)
- Flotation tailings thickening, filtration, and filtered tailings storage facility (TSF)
- Tailings backfill plant
- Fresh and reclaim water supply
- Reagent preparation and distribution
Lead–silver flotation
A dedicated lead–silver flotation circuit (rougher–cleaner cells) was included to maximize net revenue from silver production. To recover the lead–silver mineralization, a flotation stage comprising pneumatic cells in a rougher–cleaner–scavenger arrangement is proposed.
Tailings and water management
A portion of the tailings (39%) will be mixed with cement and used as structural mine backfill material in the underground operations, while the remainder (61%) will be thickened and filtered, then disposed of in a filtered TSF. Process water will be recycled as much as possible to minimize water usage.
Key reported parameters
| Parameter | Detail | Basis |
|---|---|---|
| Mine life | 14 years projected | Design basis |
| Concentrates produced | Zinc concentrate; lead–silver concentrate | Proposed design |
| Tailings backfill proportion | 39% to underground backfill | Proposed design |
| Tailings to filtered TSF | 61% | Proposed design |
| Lead–silver flotation cells | Pneumatic cells, rougher–cleaner–scavenger arrangement | Proposed design |
| Zinc flotation testwork | Locked cycle tests | Testwork |
| Lead–silver flotation testwork | Open cycle tests | Testwork |
| Zinc Zone flotation amenability | Froth flotation, commercial grades and recoveries | Testwork |
Project website: https://tinkaresources.com/home/
Technical qualifications
The design has no consideration or allowance for any expansion. The report states that the processing plant design is based on a lean, fit-for-purpose standard. The project is a greenfields site. Site development earthworks will be a major project consideration due to site limitations imposed by topography and potential geological hazards. Access improvements include a proposed new road to the site from the town of Chinche, approximately 10 km west of Yanahuanca.
*Source: Ayawilca Polymetallic Project , 2021 Technical Report, sections 1.14 Recovery Methods and 1.15 Infrastructure.*
Consolidated report summaries
The following former standalone pages about this operation were consolidated here on October 25, 2026. They are retained for source traceability; dates and figures reflect each report’s own effective date and may be superseded by the current information above.
Ayawilca Technical Report 2024
This technical report presents a Preliminary Economic Assessment for the Ayawilca Polymetallic Project in Peru, with an effective date of 28 February 2024.
Report context
This NI 43-101 Technical Report was prepared for Tinka Resources Limited on the Ayawilca Polymetallic Project, located in Peru. The report was prepared by SRK Consulting (UK) Limited with contributions from SLR, Transmin, Envis, and MineFill. The report date is April 2024, with an effective date of 28 February 2024.
Processing route
Zinc, Lead and Silver Processing
The proposed processing route for zinc, lead and silver comprises a conventional flotation flowsheet. The process begins with primary crushing, followed by grinding and classification. Lead-silver flotation is conducted first, followed by zinc flotation. Zinc concentrate and lead-silver concentrate each undergo dewatering. The tailings are dewatered for disposal.
The process design basis and process design criteria were established for the proposed zinc, lead and silver processing plant. No historical operating data for this flowsheet at the Ayawilca site was presented in the report.
Tin Processing
The proposed tin processing route comprises comminution, beneficiation, and leaching stages. The tin plant design includes these unit operations, followed by tin concentrate dewatering. Tailings are dewatered for disposal. Process design criteria were established for the proposed tin plant.
Metallurgical Testwork
Metallurgical testwork was conducted on samples from the project. Zinc recovery testwork was performed, including solid/liquid separation testwork for zinc tailings. Lead-silver recovery testwork included Phase 5B testwork and Phase 8 Silver Zone testwork. Tin recovery testwork included Phase 7 mineralogy testwork (conducted by ALS), Phase 6 tin mineralogy testwork (conducted by PMC), and Phase 7 tin metallurgical testwork (conducted by ALS). Conclusions were drawn from the tin testwork.
Metallurgical Recovery Projections
Metallurgical recovery projections were developed for the zinc plant and tin plant. Zinc concentrate quality was assessed. Deleterious elements were evaluated.
Mine Backfill
Paste backfill was proposed for mine backfill requirements. Testwork was conducted on paste backfill material, including particle size distribution analysis, rheology testing, and paste uniaxial compressive strength testing. A proposed paste mix was developed. The backfill system design and operation were described.
Key reported parameters
| Parameter | Value | Basis |
|---|---|---|
| Zinc recovery | Projections developed | Metallurgical testwork |
| Tin recovery | Projections developed | Metallurgical testwork |
| Zinc concentrate quality | Assessed | Testwork |
| Paste backfill UCS | Tested | Testwork |
| Process design criteria | Established | Proposed design |
| Solid/liquid separation testwork | Conducted | Testwork |
Project website: https://tinkaresources.com/
Technical qualifications
This report was prepared as a National Instrument 43-101 Technical Report. The quality of information, conclusions, and estimates contained herein is consistent with the level of effort involved in SRK's services, based on i) information available at the time of preparation, ii) data supplied by outside sources, and iii) the assumptions, conditions, and qualifications set forth in this report. This report is intended for use by Tinka subject to terms and conditions of its contract with SRK.
The report is a Preliminary Economic Assessment, and mineral resources that are not mineral reserves do not have demonstrated economic viability.
Source: NI 43-101 Technical Report on a Preliminary Economic Assessment of the Ayawilca Polymetallic Project, Peru, effective date 28 February 2024, report date April 2024, Section 13 (Mineral Processing and Metallurgical Testing), Section 17 (Recovery Methods), and Section 16.9 (Mine Backfill).
