Marimaca Copper (TSX: MARI) revealed on Thursday the sulphide potential of its Marimaca oxide deposit (MOD) in Chile, with drill hole MAD-22 returning 92 metres at 2.11% total copper from 140 metres, including 22 metres at 5.27% total copper, from 204 metres, in primary sulphides alone.
MAD-22 represents a geological/geotechnical diamond drill hole that was drilled from the eastern MOD through the eastern 2022 mineral resource estimate (MRE) pit wall and intersected high-grade, dominantly chalcopyrite mineralization.
The drill hole intersected the border of the magnetic susceptibility high identified in the 2020 geophysical campaign. This significant magnetic anomaly beneath the current MOD dips to the east with the same geometry as the interpreted extension of the structures that host the copper oxide mineralization at the MOD. True widths are unknown at this stage.
Combined with oxides, MAD-22 returned a full intersection of 240 metres at 1.01% total copper from surface in two separate zones (oxide and primary sulphide).
“While previous drilling into the down-dip geophysical targets identified in 2020 and 2021 intersected additional mixed and secondary sulphides at depth, MAD-22 represents the first significant primary sulphide intersection to date and could represent a primary high-grade feeder structure as interpreted in our geological model for the deposit,” VP exploration Sergio Rivera said in a news release.
“With the 2022 drill program now completed, results from MAD-22 will be considered in our exploration planning going forward,” he added.
Marimaca’s 2022 drilling campaign consisted of over 41,500 metres of reverse circulation and diamond drilling between the MOD infill and the MAMIX zone, the depth extension of the MOD. The 2022 MRE announced in October incorporates 19,580 metres of the approximate 28,374 metres of drilling completed in 2022, for a total of over 110,000 metres of drilling completed since 2016 at the MOD.
The balance of the 2022 infill drilling program will be included in a subsequent MRE planned for early 2023, with the objective of upgrading the remaining inferred resources to underpin a definitive feasibility study.
According to S&P Global Market Intelligence, the Marimaca deposit represents one of the only major copper discoveries made globally in the last decade. The project is located in northern Chile near Antofagasta.
Since its original discovery in 2016, the company has nearly doubled the oxide resource totals, now estimated at nearly 140 million tonnes at 0.48% total copper for 665,500 tonnes of contained copper in the measured and indicated category, plus 83 million tonnes at 0.39% for 322,900 tonnes of contained copper.
Shares of Marimaca Copper jumped 2.0% by 12:30 p.m. ET following the encouraging drill results. The company has a market capitalization of C$263.8 million ($193.3m).