Project of the Week: Chakana Copper

15th November 2021

 

 

This week, we head to the southern hemisphere to highlight a project making headlines with tons of recent news reports. Chakana Copper’s (TSX-V:PERU) Soledad project in Central Peru continues to deliver positive results from exploration drilling in the Ticapampa-Aija Mining District in the Ancash Province. The Soledad Project is part of a 100% owned mining claim in the Peruvian Andes comprising more than 1,100 hectares with the possibility for growth to the south through existing purchase agreements with Rosales and Barrick (Fig. 1). It’s hosted in a world class mining district, about ~35 km northwest of Antamina, one of the largest copper deposits on Earth. The Soledad project looks to be a high-grade mineralization discovery hosted in a mining-friendly country with great local infrastructure already in place, so let’s dig a bit deeper.

Figure 1. A. Geologic map of Peru indicating notable mines and exploration projects. B. Claim map of the Soldedad project area and breccia pipes. The chakana symbol, the Incan Cross, represents the directionality of a compass and the planes of existence in Incan culture. It is commonly associated with Cusco, the center of the ancient empire.

The Soledad project focuses on a suite of mineralized breccia pipes, which outcrop at the surface, where they are hosted in the 2 km thick Calipuy volcanic suite, composed of andesite lava flows and rhyolite tuffs. The breccia pipes themselves consist of broken clasts of the Calipuy suite which are cemented by a quartz-tourmaline-sulfide assemblage which host copper, gold, and silver mineralization. Breccia pipes form in magmatic systems, when hydrothermal fluids are collected at the top of a magma chamber at the liquid-rock interface called the “cupola”. Depending on the composition of the magma, this aqueous fluid becomes super-enriched in volatile elements (B, Na, K, S), percolating upwards and concentrating ore metals to form a saline, metal-rich hydrothermal fluid (e.g., Cloos, 2001). This fluid, over pressured and ready to go, is released by some geologic trigger, such as an earthquake (fault), hydraulic fracture, or pressure drop due to magma crystallization. Once that trigger hits the cupola, that fluid rockets upward, ripping through the host rock and precipitating all those shiny little copper sulfides (with gold!) along the way.

Figure 2. Model for quartz-tourmaline breccia pipe formation from Kelley et al (2019). Fluids fracture the rock above and surge upwards until the pressure of the fluid is equal to that of the rock, tapering off towards the top of the pipe.

Sounds crazy? What’s even more crazy is that there are 23 of these pipes outcropping at Soledad! Additional, unexposed pipes have been discovered from exploration drilling. This dense cluster of breccia pipes makes for an exciting exploration project with high-grade ores centralized vertical profiles. What is high grade for these pipes? How about peak grades of 55.2% copper equivalent (CuEq)? Woah, buddy — now we’re talking!

While copper is the primary resource in these pipes, that’s not all the Soledad property has to offer. Gold and silver are present at high grades, though with less consistency across core intervals than the copper mineralization. Selected results from 6 of the breccia pipes are shown in Figure 3, taken from a report published in September 2021. Certain intervals show incredible silver mineralization (up to 1,283 g/t over a 22.8 m interval in Bx6!) with accompanied by consistent ore-grade copper and gold intervals.

Figure 3. Table highlighting intervals from 6 breccia pipes in the Soledad property reported by Chakana Copper in September 2021.

So far, over 35,000 m of core have been drilled, with 26,000 more fully funded and approved in Chakana’s license area. Chakana Copper still believes there is more to discover on the Soledad property. The horizontal extent of all the pipes is not completely constrained yet, and all of the exploration targets remain open at depth. The Breccia pipe geometry is conical, with all of them widening at depth, such as the breccia pipe Bx5 cross section in Figure 4. One exciting target, the Huancarama Breccia Complex, contains a suit of breccia pipe “fingers” that outcrop at the surface and appear connected as a huge pipe at depth. A November 2021 news release (here) announced an interval of more than 100 m containing 2.13% CuEq from their most recent release of drill core data from 12 holes and nearly 3, 000 m of core from the Huancarama Breccia Complex and Bx5. While the high-grade breccia pipes are absolutely the focus of exploration and resource expansion, downward projection holds exciting prospects as well. “The upside potential is enormous”, said President and CEO David Kelley. “There is the potential for finding mineralized intrusions at depth.”

Figure 4. Cross-section and drill hole projections for Bx5 breccia pipe, as well as core examples of the mineralization. In all cases, sulfides are the last phase to precipitate during the formation of the breccia pipe, coming after the earlier quartz-tourmaline gangue. SDH21-231 (113.55m) chalcopyrite-cosalite-galena-siderite filling breccia matrix; SDH21-234 (18.00m) chalcopyrite-tourmaline-cemented shingle breccia; SDH21-243 (55.40m) chalcopyrite-pyrite-cemented chaotic shingle breccia. Core diameter is 6.35cm (HQ) in all instances. Note the open projection at the base of the section — how deep does it go?

Since 2016 when Chakana made its first moves at the Soledad property, the project has grown consistently in terms of indicated resources, with good news for potential mine development in the future. Soledad is in a prime location in the Ancash province of Peru - one of the world’s premiere mining provinces. Within a 60 km radius of two producing mines, the Antamina Mine (copper-zinc) and the Pierina Mine (gold), roads and transportation infrastructure are already available. Two mineral processing plants already active, and the Soledad property is equipped with water pumps and grid power. Peru has been a hospitable home for mining companies in the past (not withstanding recent events), and the management team at Chakana Copper is composed of experienced geologists and mining investors with a strong background in raising capital and support.

While the future is never certain, Chakana Copper’s ongoing project certainly is worth a second look. The junior exploration company has shown incredible mineralization intervals in a well-established mining district. Expect the excitement to build as the summer drilling season kicks off south of the equator in the hopes of finding even more of those blind pipes. Though the name Soledad means solitude in Spanish, it’s clear that in this mineralization field, these breccia pipes are not alone.

REFERENCES

Chakana Copper Corporate Presentation - September 6.2021, “Soledad Project: High-Grade Copper-Gold-Silver Discovery in Peru” https://www.chakanacopper.com/site/assets/files/3853/chakana_corporate_presentation_sep_6_2021.pdf

Chakana Copper - News Release October 14, 2021 - https://www.chakanacopper.com/news/2021/chakana-reports-268m-of-1.17-g-t-gold-0.55-copper-and-19.2-g-t-silver-1.48-cu-eq-in-breccia-pipe-5-from-surface-at-soledad-peru/

Chakana Copper - News Release November 1, 2021 - https://www.chakanacopper.com/news/2021/chakana-reports-113m-of-0.90-g-t-gold-0.92-copper-and-72.8-g-t-silver-2.13-cu-eq-in-huancarama-at-soledad-peru/

Cloos, M. (2001) Bubbling magma chambers, cupolas, and porphyry copper deposits. International geology review43(4), pp.285-311.

Kelley, D., Montoya, C., Park, S., Torres, V. (2021) High Grade Copper-Gold-Silver Hosted in Multiple Tourmaline Breccia Pipes, Soledad Project, Ancash, Peru. proEXPLO 2019 Conference. pp. 1-6. Conference Paper

Aaron Hantsche

View posts by Aaron Hantsche
Aaron Hantsche recently obtained his PhD in Geology from the University of Geneva in Switzerland, where he studied distal Pb-Zn skarn deposits in southern Bulgaria. Magmatic-hydrothermal deposits are his primary focus, with a bent towards geochemical vectoring tools and field geology. In addition to his work as a geologist, Aaron is a director for the science communication platform, Ore Deposits Hub. His passion for mineral deposits and geo-communication led him to join the Spotlight Mining writing team in October 2021.