Colquipucro Silver
Colquipucro Silver
The Colquipucro area is a silver (oxidized) deposit located 1.5 km north of the Ayawilca Zinc Zone. Colquipucro is a disseminated sandstone-hosted silver deposit at surface with an Indicated Mineral Resource containing 14 million ounces of silver, and an additional 13 million ounces of silver in Inferred Mineral Resources (as at May 25, 2016). The deposit remains open to the west. No drilling has taken place at Colquipucro since 2014. The deposit is potentially open pittable given the shallow depth of the silver mineralization (0 to 100 m depth).
The project also benefits from excellent local infrastructure, including road access and proximity to power lines, enhancing its development potential. Colquipucro's silver resources, combined with its strategic location and potential for further exploration upside, make it an important component of Tinka's broader efforts to develop significant silver resources in a world-class mining district.
Location and Infrastructure
Map 1: Location of the Tinka’s projects in central Peru
Geology & Mineralization
The Colquipucro silver deposit is a sandstone-hosted disseminated silver deposit with silver hosted in fractures, faults, and veins with abundant iron oxides (goethite, jarosite) and as disseminations within the pore spaces of the sandstones. The Colquipucro deposit is tentatively classified as an intermediate sulphidation epithermal deposit that became oxidized above a paleo water table. It is interpreted that Colquipucro is an oxidized form of the Silver Zone mineralization, that is, sulphides at Colquipucro have almost completely oxidized to Fe oxides and manganese-rich iron carbonates are altered to Mn-Fe oxides.
Colquipucro is hosted primarily within quartz sandstones of the Middle Goyllar Formation, with mineralization at or close to the surface. Silver mineralization at Colquipucro is oxidized, occurring with abundant iron oxides (goethite, jarosite) and manganese oxides in fractures and disseminations within pore spaces and fracture zones with no (or rare) sulphides. Historical mining for lead and silver focused on east–west-trending fracture zones that host high silver grades. The mined structures ranged from 1 m to 3 m in thickness. Mapping and sampling by Tinka of an old exploration adit that cuts across the mineralized structures demonstrated that there is lower grade disseminated silver mineralization between the fracture sets.
Colquipucro was modelled to include 10 north-dipping high-grade fracture zones, a gently dipping enriched basal zone, and a low-grade halo. Overall, the Colquipucro deposit measures 550 m in the north–south direction, 380 m in the east–west direction, and is a thickness of 75 m. Mineralization remains open down-dip to the west.
Sulphide minerals are rare, although galena is observed occasionally. The fracture-controlled mineralization is epigenetic and crosscuts the primary bedding.
Resource
Colquipucro Mineral Resources are reported within a preliminary pit shell generated in Whittle software at a cut‐off of 15 g/t Ag. Indicated Mineral Resources are estimated to total 7.4 Mt at an average grade of 60 g/t Ag containing 14.3 Moz Ag (Table 14-20). Inferred Mineral Resources are estimated to total 8.5 Mt at an average grade of 48 g/t Ag containing 13.2 Moz Ag. More than half the contained metal is from the high-grade lenses, at average grades greater than 100 g/t Ag. A small amount of mineralization was not captured by the Whittle shell.
The Mineral Resource estimate for the Colquipucro deposit used drill results available to November 17, 2014. There has been no drilling at the Colquipucro deposit since the previous Mineral Resource estimate completed in 2016 and therefore the Colquipucro Mineral Resource estimate remains unchanged.
Mineral Resources are contained within 10 north dipping high‐grade lenses, a gently dipping basal zone, and a low‐grade halo that encompasses all high‐grade lenses. Overall, the Colquipucro deposit is 550 m in the north–south direction by 380 m in the east–west direction by 75 m thick. The Colquipucro deposit is located on a topographic high and ranges between 4,160 masl to 4,360 masl elevations.
| Classification/Zone | Tonnage (Mt) | Grade (g/t Ag) | Contained Metal (Moz 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:
- CIM (2014) definitions were followed for Mineral Resources.
- Mineral Resources are reported within a preliminary pit shell and above a 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 price of US$24/oz Ag. SRK Consulting Ayawilca PEA NI43-101 TR – Main Report U31961_Tinka Ayawilca 2024 TR_240412_FINAL.docx April 2024 Page 163 of 299
- A bulk density value of 2.48 t/m3 was assigned to all blocks within resource wireframes.
- Mineral Resources have been reviewed by Katharine Masun, P.Geo., Principal Geologist with SLR Consulting (Canada) Ltd., who is a Qualified Person as defined in NI 43-101.
- Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
- Numbers may not add or multiply due to rounding