The Ayawilca Silver Zone is a silver-rich vein structure which truncates the northern edge of the massive sulphide bodies at South Ayawilca. It was delineated by drilling during the 2022-23 drill campaign. The Silver Zone is hosted within the Pucara limestones and is a carbonate-rich (siderite and rhodochrosite) vein structure that contains base metal sulphides (sphalerite and galena) and silver sulphides (including acanthite). The structure has been identified with drilling over a strike length of about 500 metres, and to a depth of about 250 metres. The Silver Zone remains open along strike in both directions and at depth.
The Mineral Resource estimate for the Silver Zone was provided by SLR Consulting (Canada) as of January 1, 2024. See Table 2.
Table 2. Ayawilca Silver Zone Mineral Resources as of January 1, 2024
Classification | Tonnage Mt | NSR $/t | Grade | Contained Metal |
Zn % | Ag g/t | Pb % | In g/t | Mlb Zn | Moz Ag | Mlb Pb | t In |
Inferred | 1.0 | 100 | 1.54 | 111.4 | 0.5 | 3 | 35 | 3.7 | 12 | 3 |
Notes:
- CIM (2014) definitions were followed for Mineral Resources.
- The Mineral Resources have been reported within underground reporting shapes generated with Deswik Stope Optimizer (DSO) using a net smelter return (NSR) cut-off value of US$50/t.
- NSR value was based on estimated metallurgical recoveries, assumed metal prices, and smelter terms, which include payable factors, treatment charges, penalties, and refining charges. The NSR used for reporting is based on the following:
- Long term metal prices of US$1.40/lb Zn, US$25/oz Ag, and US$1.10/lb Pb.
- Net metallurgical recoveries of 77% Zn, 85% Ag, and 85% Pb.
- The NSR value for each block was calculated using the following NSR factors: US$15.10 per % Zn, US$0.62 per gram Ag, and US$14.48 per % Pb.
- The NSR value was calculated using the following formula: NSR = Zn(%)*US$15.10+Ag(g/t)*US$0.62+Pb(%)*US$14.48.
- Bulk densities were assigned to blocks by interpolation and remaining blocks by regression of Fe assay data or average sample data. The average bulk density is 3.18 t/m3.
- Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
- Numbers may not add due to rounding.