The Curibaya property comprises of approximately 11,000 hectares situated in a copper porphyry belt that hosts some of Peru’s largest porphyry deposits, including Freeport McMoRan’s Cerro Verde deposit, Southern Copper’s Cuajone and Toquepala deposits and Anglo American’s Quellaveco deposit. The project is the first major epithermal occurence in this belt, which covers the regional Incapuquio fault zone and subsidiary structures, which are interpreted as one of the fundamental controls for both epithermal and porphyry styles of mineralization within the region. Importantly, the licenses host a number of cross structures to the Incapuquio fault zone that are considered highly prospective. Initial surface sampling programs at Curibaya have returned numerous high-grade samples of silver, gold and copper over a 4 x 5 kilometre (km) alteration system.
The Curibaya Project is located 48 km north-northeast of the provincial capital, Tacna, and is accessible by road in 1.5 hours.
Rock grab sampling at the Curibaya project has returned grades of up to 298,000 g/t silver and 934 g/t gold, with samples spread across a 4 x 5 km alteration system. Rock grab sample highlights are shown in the table to the right using cut-off grades of 500 g/t Ag and 2 g/t Au.
Tier One has identified the age of mineralization at Curibaya to be Paleocene, ranging from 55 to 61 million years. This is equivalent to several world-class deposits in the southern Peru porphyry belt, including Quellaveco (Anglo American), Toquepala (Southern Copper Corp.) and Cuajone (Southern Copper Corp.). Tier One's technical team believes the Paleocene age date of the mineralization, along with the large precious metal budget observed within high-grade veins over a 4 x 5 kilometre alteration system, support the potential for a world-class discovery at the Curibaya project.
At this early stage, the Company’s technical team believes there are both precious metal intermediate sulphidation epithermal and copper porphyry targets.
Geologic Context of Vein Mineralization:
Tier One Silver was spun out from Auryn Resources in October 2020, therefore inheriting ownership of the Curibaya project and relating obligations. Auryn had a 100% interest in the Curibaya concession (acquired in 2015) and the Sambalay and Salvador concessions (acquired in 2019). The Sambalay and Salvador concessions are subject to certain historical NSR royalties.
Under the Mining Concessions Transfer Agreement (the “Transfer Agreement”) entered with Wild Acre Metals (Peru) S.A.C. dated August 2, 2019, the Company paid US$250,000 for the transfer of the Sambalay and Salvador concessions, in favor of the Company, upon recording of the Transfer Agreement with the Peruvian Public Registry. The Sambalay concessions are subject to a 1.5% NSR royalty in favor of each of Teck Peru S.A.C. (“Teck”) and Compania de Exploraciones Orion S.A. (“Orion”). One third, or 0.5%, of the Teck NSR royalty is buyable for US$1.0 million. The Salvador concessions are subject to a 2% NSR royalty and a US$2.0 million production payment, payable at the time a production decision is made, and to secure payment of such consideration a legal mortgage in favor of Teck is recorded in the registry files of the Salvador concessions.
Curibaya Age Dating, 2020
A total of four samples of altered volcanic rocks were collected for Ar-Ar geochronology analysis. Samples were sent to Pacific Centre for Isotopic and Geochemical Research, University of British Columbia, in Vancouver, Canada. They were analyzed through neutron irradiation at McMaster Nuclear Reactor in Hamilton, Ontario, and a VG5400 mass spectrometry. The best statistically justified plateau and plateau ages picked. Two out of four samples had isochrons sufficient for plateau age determination.
PERU Rocks Q4 2020 (Curibaya)
Approximately 2-3kg of material was collected for analysis and sent to ALS Lab in Arequipa, Peru for preparation and then to Lima, Peru for analysis. All samples are assayed using 30g nominal weight fire assay with ICP finish (Au-ICP21) and multi-element four acid digest ICP-AES/ICP-MS method (ME-MS61). Where ICP21 results were > 3 g/t Au the assay were repeated with 30g nominal weight fire assay with gravimetric finish (Au-GRA21). Where MS61 results were greater or near 10,000 ppm Cu, 10,000ppm Pb or 100ppm Ag the assay were repeated with ore grade four acid digest method (Cu,Pb,Ag-OG62). Where OG62 results were greater or near 1500ppm Ag the assay were repeated with 30g nominal weight fire assay with gravimetric finish (Ag-GRA21). Where Ag-GRA21 results were greater or near 10,000ppm Ag the assay were repeated with fire assay with gravimetric finish for concentrate (Ag-CON01). QA/QC programs for 2019/2020 rock samples using company and lab duplicates, standards and blanks indicate good accuracy and precision in a large majority of standards assayed.