Colquipucro

Silver Mineral Resources

As of November 26, 2018, the Mineral Resources at Colquipucro are reported within a preliminary pit shell and above a cut-off grade of 60 g/t Ag for the high grade lenses and 15 g/t Ag for the low grade halo mineralization. The cut-off grade is based on a price of US$24/oz Ag.The Mineral Resources were estimated by Roscoe Postle Associates Inc. (RPA) of Toronto, Canada. The reader is advised to review the full NI 43-101 Report, dated June 26, 2019, on SEDAR.com for details of resource estimates and assumptions.

The Colquipucro Silver deposit is located about 2 kilometres north-northwest of the Ayawilca Zinc and Tin Zones. Sixty five percent (65%) of the silver inventory at Colquipucro occurs within a series of shallowly-dipping high-grade lenses, mostly lying very near to surface.

HIGH-GRADE LENSES

Indicated Mineral Resources: 2.9 million tonnes at 112 g/t silver for 10.4 million ounces of contained silver.

Inferred Mineral Resources: 2.2 million tonnes at 105 g/t silver for 7.5 million ounces of contained silver.


The Mineral Resource estimate for the combined high-grade lenses and low-grade halo mineralization at Colquipucro is as follows:

TOTAL COLQUIPUCRO MINERAL RESOURCES

Indicated Mineral Resources: 7.4 million tonnes at 60 g/t silver for 14.3 million ounces of contained silver.

Inferred Mineral Resources: 8.5 million tonnes at 48 g/t silver for 13.2 million ounces contained silver.

Mineralization at Colquipucro is oxidized and disseminated within quartzite sandstone outcrops (from 0 metres to 80 metres depth). The silver deposit is likely to be amenable to conventional leaching. Preliminary metallurgical test work indicates good silver recoveries when the material is crushed, and recoveries improve in the higher grade mineralization.

Historically, narrow silver-rich veins were mined periodically at a very small scale. A previous explorer developed several tunnels into Colquipucro hill and drilled four holes on the edge of the property. No other exploration was done prior to Tinka acquiring the property through staking in 2005.

Note: The cut-off grade is based on a price of US$24/oz Ag. Silver recoveries for low-grade and high-grade mineralization were estimated to be 50% and 80%, respectively. 

Silver oxide mineralization

Silver mineralization is hosted by quartzite sandstones covering an area approximately 450 m north-south by 200 m east-west and is up to 80 metres thick. The silver oxide mineralization occurs in fractured rocks with iron oxides (after oxidation of sulphides) with or without manganese oxides. Sulphides are rare, when present are pyrite or galena. Mineralization is enriched in east-west trending steep-dipping fracture zones which dip at moderate angles to the north. Beneath the sandstone lies the Pucara limestone which has has potential to host significant zinc mineralization, underneath the sandstone.

Tinka has completed 8,003 metres in 45 diamond drill holes at the project in a number of programs since 2008. The most recent drill program was completed Q4 2014. Selected drill hole highlights 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;
  • CDD43: 39 metres at 200 g/t silver from 104 metres depth.