Colqui Silver Zone
Overview
The Colqui Silver Zone (historically known as Colquipucro, or “pot of silver” in the Quechua language) is located 1.5 kilometres north of the Ayawilca Zinc Zone, with both deposits connected by the NNW-trending Colquipucro Fault (see Figure 1).
Silver was exploited from Colquipucro at a small scale in the early 19th century. Tinka claimed several mining concessions when the area became available in 2006, and has since completed 8,000 metres of drilling in 45 holes at the Colqui Silver Zone.
Silver Resources (oxide):
Mineral resources at the Colqui Silver Zone are estimated to contain (see Table 1 below):
- 14.3 million ounces of silver in the Indicated category and 13.2 million ounces in the Inferred category.
The resources remain open to the west.
Oxidized silver mineralization occurs in fractures and disseminations hosted by sandstones of the Gollyar Group from surface to a depth of ~80 metres. Silver is concentrated along east-west trending fracture zones occurring with iron oxides (from the oxidation of original sulphides) with manganese and disseminated within favourable units of the quartz sandstones, which are gently east dipping. Given the flat-dipping and shallow nature of the mineralization, the silver deposit is potentially amenable to open pit mining and conventional leaching. Preliminary metallurgical test work indicates strong silver recoveries from leach tests (including both bottle rolls and column leach tests) from crushed samples.
Selected drill hole highlights from the Colqui Silver Zone include:
- CDD4: 32 metres at 265 g/t silver from 96 metres depth;
- CDD11: 58 metres at 123 g/t silver from 88 metres depth;
- CDD14: 70 metres at 123 g/t silver from 18 metres depth;
- CDD19: 52 metres at 128 g/t silver from 16 metres depth;
- CDD23: 80 metres at 105 g/t silver from 12 metres depth;
- CDD30: 104 metres at 96 g/t silver from 2 metres depth; and
- CDD43: 39 metres at 200 g/t silver from 104 metres depth.
Table 1 - Colqui Silver Zone Mineral Resource Estimate as of May 25, 2016
Zone and Confidence Classification | Tonnage | Ag | Contained Ag |
|---|---|---|---|
Indicated |
|
|
|
High Grade Lenses | 2.9 | 112 | 10.4 |
Low Grade Halo | 4.5 | 27 | 3.9 |
Total Indicated | 7.4 | 60 | 14.3 |
Inferred |
|
|
|
High Grade Lenses | 2.2 | 105 | 7.5 |
Low Grade Halo | 6.2 | 28 | 5.7 |
Total Inferred | 8.5 | 48 | 13.2 |
Notes:
- The Qualified Person for the estimate is Ms. Dorota El Rassi, P.Eng., an RPA employee. Mineral Resources have an effective date of May 25, 2016.
- Mineral Resources are reported using the 2014 CIM Definition Standards. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
- Mineral Resources are reported within a preliminary pit-shell and above a reporting cut-off grade of 15 g/t Ag for the Low-Grade Halo and 60 g/t Ag for the High-Grade Lenses.
- The cut-off grade is based on a silver price of US$24/oz Ag.
- Numbers may not add due to rounding.