The regional setting, geometry, and zinc mineralogy indicates that the Zinc and Tin Zones of the Ayawilca deposit are CRDs, of which there are several other type examplesin central Peru (e.g., Cerro de Pasco, Morococha, Colquijirca, and San Gregorio). These deposits typically develop when hydrothermal fluids replace carbonate rocks proximal to an intrusive body, although in some cases the causative intrusive body is not observed. CRDs are considered more distal from the source than porphyry and skarn deposits, but closer to the source than intermediate- (or low-) sulphidation epithermal precious metals deposits.

The Ayawilca deposit differs from most other CRDs in central Peru in that there is an early tin–copper mineralization event associated with pyrrhotite. The QPs note that early pyrrhotite tin–copper mineralization is reported at the Cerro de Pasco deposit, although apparently it is not so well developed as at Ayawilca.

The oldest rocks mapped on the Property are phyllite metamorphic rocks which belong to the Devonian Excelsior Group. These outcrop in the north–central and eastern portions of the Project area, and consist of light coloured quartz–sericite–chlorite phyllite and minor graphitic schist. Foliations strike generally northwest–southeast with gentle to moderate dips to the southwest and northeast. The large phyllite outcrop is interpreted to be the core of an anticline (basement high) bounded by two sub-parallel northwest-trending Ande ........

The Ayawilca deposit is planned to be mined using underground mining methods. To define the mining method, the University of British Columbia (UBC) mining method selection system was applied, together with consideration of aspects such as safety, the geometry of the resources, the distribution of grades, the scale of production and mining costs. Based on this analyses, two suitable mining methods were selected:
- Overhand cut-and-fill (OCF) with pillars;
- Sub-level stoping (SLS).

The mining strategy involves dividing the deposit into five zones by spatial location and by mining method:
- OCF with pillars: Central and East areas;
- SLS: West, South areas and Silver Zones.
The netsmelter return cut-off was defined at US$65/t, asit covers mining, processing, general and administrative costs and sustaining capital costs, and was determined to be a reasonable balance considering the margin per tonne of material mined while still having a reasonable resource extraction and mine life.

The production rate was set at 8,500 t/d after considering the sustainable rate achievable from the multiple mining areas. Optimizations were completed using the mineable shape optimiser (MSO) unit within Datamine software. The SMU length and height were fixed values, whereas the width varied by zone and mineralized structure, from 5–45 m. Sections of 5 x 5 m were defined for the development drives and the Central area pillars.

A m ........

- subscription is required.

- subscription is required.