Max Resources (TSXV: MXR; US-OTC:MXROF) has discovered a high-grade outcrop at its wholly owned Cesar copper-silver project in northeastern Colombia, about 140 km north of the capital, Bogota.
The Cesar project comprises two mineralized zones, AM North and AM South. Assays from the AM North-2 mineralized area within the AM North zone of the project, recently returned 24.8% copper and 230 grams silver per tonne over a 4 metre by 1 metre rock chip panel.
The discovery comes only a week after the company reported a 1 metre continous rock chip sample grading 10.4% copper and 88 grams silver per tonne in the AM North-1 area, around 1.8 km from the AM North-2 find. Grades at the AM South zone include 5.4% copper and 63 grams silver per tonne and the zone is open-ended over 5 kilometres.
“Our geologists made the discovery as they were returning from the AM South zone and collected rock chip samples from the AM North-1 and AM North-2 mineralized areas in one day,” Brett Matich, CEO of Max Resources, said in a telephone interview with The Northern Miner. “It was extremely unexpected to see not only the 24% grade but also the 10% grade from assays tested the week before.”
Although the samples were collected at the same time, because the grade returned from AM North-2 was so high, the company re-assayed the samples to ensure they were correct, hence the delay in reporting the higher-grade strike, Matich said.
The mineralization extends 35 km between the AM North and AM South, and comprises malachite, azurite and chalcocite within the sandstone and resembles a large horizontal sheet that is open-ended and dips 20 degrees northwest along the zone.
“Although it would appear that the two structures are linked with continuous rock chips wherever you look, we aren’t expecting the same high grade across the full 1.8 km length,” Matich said. “And so we are targeting a grade of plus 1.5% copper with associated silver along a 40-km-long target zone joining AM South and AM North.”
An initial exploration program at the Cesar project in November 2019 identified 19 distinct mineralized copper occurrences over an area of 9 sq. km and open in all directions. A Phase 1 exploration program previously returned grab sample assays ranging from 0.3% to 4.2% copper, with 34 out of 43 samples assaying in excess of 1%, 15 samples showing over 2% and four samples returning over 3% copper.
The Cesar project contains a high-grade stratabound copper and silver mineralized zone that is hosted in a well bedded sandstone-siltstone that the company believes may be similar to the Kupferschiefer in Poland. Kupferschiefer is an extensive sedimentary stratabound system that spans the southern Permian basin of Poland covering an area of over 600,000 sq. km.
The mineralized zones at Cesar are characterized by Jurassic sediments and volcaniclastics that extend the length of northern South America and also host significant stratabound copper and silver mineralization in Ecuador and Peru. The deposit lies along a historic 120 km copper-belt, within a coal and oil and gas district. The region contains extensive infrastructure, including major oil and gas operations, coal mines, ports, railways and roadways.
With the ongoing revolution in green technologies, and particularly the exponential growth in solar photovoltaics and hybrid and electric vehicles, the global demand for copper and silver over the next decade and beyond will increase sharply. Therefore, deposits like Cesar will become increasingly important to the production of new and renewable technologies, the company said.
Because of the extensive surface cover, Max Resources is using rock chip sampling to define the mineralized structure, the continuity of its thickness, and the strike length, to estimate Cesar’s potential size before commencing drilling.
Given that the company only began exploration work in November last year, Matich is confident that further discoveries will follow these early-stage successes at AM North and AM South in 2020.
“The current discoveries support our belief that Cesar is a large-scale copper-silver mineralized zone,” said Matich. “Our team is currently undertaking further rock chip sampling to further our knowledge of the mineralization in the area, with the hope of expanding the project into a world-class copper and silver producing region.”
(This story first appeared in The Northern Miner on March 9, 2020)