Broken Hill Mines to increase Rasp mill feed with high-grade Main Lode ore

• Broken Hill Mines completes underground access to Main Lode ore body with ore delivery targeted for November 2025
• Breakthrough provides first direct mining access to high-grade Blackwoods deposit since mid-1970s
• Infill and extensional drilling returns high-grade zinc and silver including 2.1m at 2103g/t silver equivalent

Special Report: Broken Hill Mines is poised to add a new source of high-grade polymetallic feed for its operating Rasp Mill in Far West NSW after completing underground development to access the Main Lode ore body.

The company is on track to deliver ore from the Main Lode by November 2025 to supplement existing feed from the Western Mineralisation ore body that has been the primary source of ore to the Broken Hill processing plant for more than a decade.

Development of Main Lode and future development of the Pinnacles ore body are key initiatives of Broken Hill Mines’ (ASX:BHM) strategy to fully utilise the 750,000tpa plant at Rasp mine.

Adding interest, drilling of the Blackwoods and British deposits of the Main Lode – which are set to be mined next – returned very high-grade silver and zinc assays including several intercepts outside the current resource of 670,000t at 18.7% zinc equivalent or 628g/t silver equivalent.

Notable results include:

• 2.1m grading 62.5% ZnEq or 2103g/t AgEq (MLDD4900);
• 4.3m at 57% ZnEq or 1919g/t AgEq (MLDD4902); and
• 4.8m at 51.4% ZnEq or 1706g/t AgEq (MLDD4867).

Rasp mining

BHM acquired the Rasp mine and Pinnacles asset at Broken Hill in late October 2024 under its previous guise as Coolabah Metals.

Since then, it has been undertaking an expansion project to bring online a second ore body, the Blackwoods deposit, within the high-grade Main Lode ore body to supplement feed from the Western Mineralisation ore body.

It has now completed breakthrough (link up) of the Main Lode incline/decline after its underground contractor Byrnecut completed 1000m of development.

This provides direct underground mining access to the Blackwoods deposit for the first time since the mid-1970s.

BHM notes the incline/decline system, which connects to the existing Rasp portal, significantly reduces cycle times and enhances ventilation, resulting in improved productivity for mining, development and exploration activities along Main Lode.

Ramp up of ore feed from Blackwoods is targeted to occur over the course of FY26, with additional stoping operations planned in Q1 of 2026, after expansion of existing project approvals.

In addition, gold is yet to be systematically assayed at the Rasp Mine, which will be undertaken by BHM in the coming months.

Drill results

Blackwoods is the first Main Lode resource north of the newly completed incline/decline.

It provides untapped stoping potential in good ground conditions with remnant mining opportunities outside the current resource that can also be exploited.

Already, the results from the first round of infill and extension drilling at the Blackwoods and British deposits have improved resource confidence while confirming extension potential.

Further extension potential exists in the southern uppers area of Blackwoods as well as opportunity in the northern section of the orebody, which remains open at depth.

The British deposit has extension potential to the south (back towards Blackwoods/Thompsons) and remains open to the north and at depth.

Results from the 63-hole drilling campaign are expected to add to the current resource for the Blackwoods and British deposits.

Looking ahead, BHM will plan future drill programs to test the potential extensions at both Blackwoods and British, as well as the remnant mining potential in the adjacent Thompson’s deposit.

An updated resource for the broader Rasp mine is expected in Q1 2026.

This article was developed in collaboration with Broken Hill Mines, a Stockhead advertiser at the time of publishing.

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.