Developer Marimaca Copper (TSX: MARI; US-OTC: CROJF) has launched an up to date useful resource estimate for its namesake undertaking within the Antofagasta area of northern Chile, confirming it as one of many greatest copper discoveries of the previous 10 years.
The Vancouver-based firm stories a 98% enhance within the measured and indicated useful resource tonnage of the Marimaca Oxide Deposit (MOD). It entails 139.6 million tonnes grading 0.48% complete copper (0.3% acid soluble copper) for about 665,000 tonnes of contained steel.
The inferred useful resource grew by 92% to 82.7 million tonnes grading 0.39% complete copper (0.16% acid-soluble copper) for about 323,000 tonnes of steel. The corporate used a US$4 per lb. copper value to estimate the brand new useful resource.
President and CEO Haydn Locke tells The Northern Miner the numerous undertaking milestone opens the door for the primary part growth’s manufacturing scale to extend in future growth research. He suggests the corporate will contemplate increased manufacturing instances of fifty,000 and 60,000 tonnes per 12 months copper cathode in its feasibility research for the undertaking, in contrast with the 36,000 tonnes per 12 months life-of-mine common specified by the June 2020 preliminary financial evaluation (PEA).
Importantly, Locke says the high-grade core, which contains the primary six years of the PEA mine life, is anticipated to stay intact and accessible in a scaled-up growth state of affairs. It contains about 50 million tonnes grading 0.7% complete copper ranging from floor in inexperienced oxide for about 350,000 tonnes of contained steel.
The mine plan requires a low strip ratio of 1:1 maintained in constraining the pit shell, with all sources captured in a single steady pit. “Low pre-strip and LOM strip ratio drive important value benefits,” says Locke in an interview.
“Our financial research up to now confirmed comparatively low sensitivity to adjustments within the underlying copper value assumption, indicating a excessive return on funding of 2021 and 2022 drilling campaigns as they pertained to useful resource development for the MOD,” says Locke.
In August 2020, the corporate launched a PEA for Marimaca, which confirmed its potential to be a low capital value, high-margin copper mine. Locke factors out that it’s considerably aided by its location with easy accessibility to infrastructure, together with energy, transport and water, in addition to a highly-skilled native workforce and easy logistics.
Based on the PEA, Marimaca has a low capital value of US$285 million. Working prices additionally fall within the backside 15% of the all-in sustaining value curve at US$1.29 per lb. over the mine life, which offers a money margin of 65% at US$3.70 per lb. copper.
Exploration upside
Locke sees clear alternatives for extra useful resource enlargement. Marimaca says mineralization on the MOD stays open to the east, southeast, and down-plunge, whereas satellite tv for pc targets found in 2021, lower than 5 km away from the open pit – Mercedes, Cindy, and Robles – present high-probability targets for additional mine life extension.
The manager factors to a big quantity of remaining 2022 drilling to be captured in one other deliberate early 2023 useful resource replace, concentrating on many of the tonnes to be captured within the measured and indicated classes to help the eventual improve to reserves.
Importantly, Locke says the group has recognized the potential for a brand new, higher-grade inexperienced oxide zone within the shallow north and north-eastern areas of the MOD, which may have constructive grade implications for the ultimate useful resource estimate early subsequent 12 months.
“Now we have accomplished one other 28,000 metres of drilling for which we’re ready on outcomes. These will probably be launched over the approaching months and integrated right into a remaining MRE in early 2023, which can kind the idea of our growth plans for the undertaking,” says Locke.
Sergio Rivera, Marimaca’s VP of exploration, made the preliminary discovery in 2017. His hunch that this space may host important mineralization was confirmed just a few months later when a one-in-a-hundred-year rainfall washed the Atacama mud away to disclose the green-coloured mountainside at Marimaca.
Early in September, Osisko Gold Royalties (TSX: OR; NYSE: OR) acquired a 1% web smelter return royalty masking the then-known mineralization and potential exploration areas that represent the undertaking for US$15.5 million.
