Sandfire Resources taps RBC to offload US copper asset

By the Editorial Team · Friday, August 28, 2026

Australian copper miner Sandfire Resources has appointed Royal Bank of Canada to manage the sale of its fully permitted Black Butte copper project in Montana, which features high-grade deposits and a planned underground mine with an eight-year life. The sale aims to recoup Sandfire’s $85 million investment amid rising copper prices and is expected to attract mainly US-based buyers due to the project’s strategic location and favorable resource outlook.

Australian copper miner Sandfire Resources has engaged Royal Bank of Canada to handle the sale of its Black Butte copper project located in Montana, United States. The Black Butte asset, held through Sandfire Resources America and listed on the Toronto Stock Exchange with a market capitalization of approximately $225 million, is majority-owned by Sandfire Resources, an ASX-listed company valued at around $1 billion.

The Black Butte project is recognized as one of the highest-grade undeveloped copper deposits in the US. It occupies ranch land in Meagher County and is fully permitted, positioning it as a potentially significant economic contributor to the central Montana region. A December feasibility study for the project’s primary Johnny Lee deposit confirmed the feasibility of a low-technical-risk underground mine coupled with a conventional processing plant. The plant is designed to process 1.2 million tonnes of ore annually, producing an estimated 35,000 tonnes of contained copper per year during the first four years and averaging 29,000 tonnes per year over an anticipated eight-year mine life.

Updated resource estimates support the development plans, with Johnny Lee holding a mineral resource of 22.3 million tonnes grading 2.4% copper and an ore reserve of 9.5 million tonnes at 2.9% copper. The nearby Lowry deposit, situated within three kilometers of Johnny Lee and potentially accessible via planned underground infrastructure, contains an additional 9.3 million tonnes of ore at 2.3% copper. This proximity offers an opportunity to extend the mine’s lifespan with relatively low additional capital expenditure.

Sandfire Resources has undertaken a strategic review of the Black Butte project and reportedly placed the asset on the market in March. The sale process is currently in its second phase. While several Australian-listed companies evaluated the opportunity, they reportedly chose not to proceed with a bid, and industry sources suggest that the project is likely to attract interest primarily from US-based buyers.

Since acquiring and developing the project, Sandfire has invested approximately $85 million and aims to recover this outlay through the sale. Additional capital investments will be required to advance the project to production.

The decision to divest follows a notable increase in copper prices, which have reached roughly $6.60 per pound amid rising demand from construction and manufacturing sectors and concerns over US import tariffs.

This article was reported by synthesizing coverage from multiple independent news outlets to present a balanced, unbiased account. Read about our editorial standards. Spotted an error? Let us know.