Australia-headquartered miner Sandfire Resources is continuing to support the Sandfire Americas team to progress the Black Butte project, in Montana, CEO Brendan Harris said on Tuesday.

Sandfire holds its interest in Black Butte through an 87% equity stake in TSX-V-listed Sandfire Resources America.

In a critical milestone for the Black Butte project, Sandfire America last month received a positive ruling from the Montana Supreme Court, reinstating the mine operating permit for the Black Butte project.

Harris said this was understood to have removed the last major impediment to the development of the project in its current form.

Harris emphasised that while this was a significant step forward, the ultimate decision to proceed would heavily weigh on the project’s economics. Therefore, Sandfire was actively conducting targeted exploration drilling to enhance the high-grade resource at the Johnny Lee deposit.

The ongoing 2024 drill programme is focused on upgrading and expanding the Johnny Lee Lower Copper Zone resource, which at last estimate consists of a measured and indicated resource of 1.2-million tonnes grading 6.8% copper and an inferred resource of 0.5-million tonnes of 5.9% copper. Since December 2023, the company has drilled about 4 420 m of a planned 20 000-m drill programme. 

Sandfire Resources America on Tuesday announced some high-grade copper intersections from its winter exploration drilling programme. Notable highlights include hole SC24-279, which intercepted 5.37 m of 10.2% copper and hole SC24-284 which intercepted 6.26 m of 10.7% copper.   

The Johnny Lee deposit has a measured and indicated mineral resource of 10.9-million tonnes at an average copper grade of 2.9% for 311 000 t of contained copper at a 1.0% copper cutoff grade, and an inferred mineral resource of 2.7-million tonnes at an average grade of 3.0% for 80 000 t of contained copper.