The mining newspaper for Alaska and Canada's North
The mining newspaper for Alaska and Canada's North
North of 60 Mining News - December 16, 2024
A drill tests a Storm Copper resource expansion target.
This sample of massive chalcocite (copper sulfide) collected from the Hailstorm discovery within the Storm resource area averages more than 50% copper (the upper detection limit of the assay technique used).
Recent testing confirms the potential of using ore sorting to separate high-grade copper minerals from the host rock at Storm.
In another large step toward its goal of establishing a low-cost mining operation capable of directly shipping high-grade ore from Storm Copper to global markets, American West Metals Ltd. reported a major expansion of the Australian Joint Ore Reserves Committee- (JORC) compliant resources at its project in Nunavut.
"The updated JORC-compliant MRE (mineral resource estimate for the Storm Project has delivered what we believe will be the foundations for Canada's next copper mining camp," said American West Metals Managing Director Dave O'Neill.
According to the new calculation, six deposits at Storm – Cyclone, Chinook, Corona, Cirrus, Thunder, and Lightening Ridge – host 20.61 million metric tons of JORC-compliant indicated and inferred resources averaging 1.11% (504 million pounds) copper and 3.34 grams per metric ton (2.2 million ounces) silver.
While this marks a roughly 18% expansion over the inaugural resource calculated earlier this year, the true value for establishing a direct shipping ore (DSO) mine at Storm is reflected in the substantial expansion of resources that have been upgraded to the higher confidence indicated category.
According to the new calculation, the Cyclone and Chinook deposits host 10.62 million metric tons of indicated resources averaging 1.3% (304 million lb) copper and 4.13 g/t (1.4 million oz) silver – a 117% increase over the previous estimate.
"This year's drilling has significantly derisked the Storm resource and moved a lot of the copper metal at the Cyclone and Chinook deposits into the indicated JORC category," said O'Neill. "This classification is essential for permitting and the ongoing assessment of the project and allows us to develop robust mine plans and economic models."
Given the style and grade of copper mineralization at Storm, coupled with the project being located near tidewater on a Nunavut island along Northwest Passage shipping lanes, American West believes ore mined from the high-grade deposits being outlined there could easily be upgraded with ore sorting technology to a product ready to deliver to market.
The dominant copper mineral within the Storm deposits is chalcocite, a dark grey and heavy copper sulfide mineral that contains 79.8% copper. The coarse chalcocite veins and breccias are hosted within a light grey or brown dolomite (a type of limestone) with a specific gravity of around 2.85%, which is half of the roughly 5.7% specific gravity for chalcocite.
The large difference in physical properties indicates the potential to easily separate the heavy and dark-colored copper mineralization from the much lighter host rocks.
Recent testing confirms the potential of using ore sorting to separate high-grade copper minerals from the host rock at Storm.
Ore sorting, which uses a variety of sensors and algorithms to identify material properties and then separate them in real-time, has the potential to upgrade the Storm Copper mineralization to a DSO.
Metallurgical testing completed earlier this year indicates that an X-ray transmission (XRT) ore sorter and an inline pressure jig could upgrade copper mineralization at Storm to a direct shipping ore containing roughly 20% copper.
Without the costs and complexities associated with a full-scale processing plant and tailings storage facility, the ore sorter and jig offer a pathway to quickly deliver copper needed for the energy transition to market.
"The process of generating DSO at Storm is amazingly simple and highlights our company's focus on generating ESG sensitive and low capital development solutions," O'Neill said earlier this year. "Storm Copper now stands out as one of the very few, and highest-grade DSO copper opportunities globally."
American West's 2024 exploration also underscored the strong potential to build upon the foundation laid by the expansion of indicated resources within the Cyclone and Chinook deposits.
This high-grade copper resource building begins with the inclusion of Thunder and Lightening Ridge deposits to the newest MRE.
Lightening Ridge, which lies in a small gap between the Chinook and Corona deposits, hosts 491,000 metric tons of inferred resource averaging 0.93% (10 million lb) copper and 4.4 g/t (69,000 oz) silver.
The larger Thunder deposit, which is about 700 meters west of Chinook and 1,000 meters south of Cyclone, hosts 1.82 million metric tons of inferred resource averaging 1.04% (42 million lb) copper and 1.6 g/t (90,800 oz) silver.
This sample of massive chalcocite (copper sulfide) collected from the Hailstorm discovery within the Storm resource area averages more than 50% copper (the upper detection limit of the assay technique used).
The high-grade Gap and Hailstorm discoveries about 1,000 meters northwest of the Thunder deposit, along with a deeper fault offset extension of the Cyclone deposit, are not included in the resource estimate. These and other targets within a roughly 10-square-kilometer (3.9 square-mile) area of the much larger Storm property offer the promise of immediate resource growth.
The resource-building potential at Storm was further underscored by a reconnaissance program carried out this summer that discovered and confirmed five copper prospects spanning the 68-mile- (110 kilometers) long mineralized belt covered by the district-scale property.
American West plans to continue to explore these regional targets while advancing toward the development of a DSO operation at the deposits outlined within the Storm resource area.
"Accelerating the definition of further copper resources within Storm and the regional areas will be a focus of future drilling programs," O'Neill said.
American West says the updated Storm resource is already being incorporated into a revised plan for developing a DSO mining operation at Storm.
Over his more than 16 years of covering mining and mineral exploration, Shane has become renowned for his ability to report on the sector in a way that is technically sound enough to inform industry insiders while being easy to understand by a wider audience.
Reader Comments(0)