Broken Hill Mines Links 1,600m Centenary Strike With 173g/t Silver Discovery
Broken Hill Mines confirms major discovery as thick, high-grade Centenary intercepts join up 1,600m strike
Broken Hill Mines (ASX: BHM) has confirmed a major new discovery of bulk tonnage, high-grade silver-lead-zinc mineralisation in the Centenary Zone at its 100%-owned Rasp Mine. The announcement marks the first ever successful targeted drilling below the Globe-Vauxhall Shear at Rasp, with two new holes returning wide, high-grade intercepts outside the existing Mineral Resource Estimate (MRE), connecting the northern and southern portions of Centenary across the full ~1,600m strike length.
Standout intercepts include assays up to 173g/t Ag — approximately 4.4x higher in grade than the historical Centenary MRE. Centenary sits approximately 250m from existing Rasp operations, positioning the discovery as a low capital-intensity growth pathway within practical reach of current infrastructure. BHM is targeting an MRE upgrade for Centenary and the broader Rasp Mine in Q4 CY26.
Inside the drill results — what the assays revealed
The Company’s 2nd and 3rd holes in its first Centenary drill program have delivered further validation of the discovery. Critically, hole WMDD6400W1 sits outside the existing MRE and connects the two previously separate portions of the deposit across the full strike length. The silver grade within WMDD6400W1 is anomalous, recording approximately 4.4x the existing Centenary MRE grade.
This announcement builds on the 23 July 2026 result from WMDD6391, which returned a thick, high-grade intercept of 25.8m @ 11.7% ZnEq, 323g/t AgEq from 415.1m. That intercept was approximately 500% wider and 27% higher in grade than modelled by the 2024 Inferred MRE at that location.
| Hole ID | Interval | ZnEq (%) | AgEq (g/t) | Key Metals (Ag/Pb/Zn/Cu) |
|---|---|---|---|---|
| WMDD6400W1 | 17.8m from 420m | 10.1% | 280g/t | 83g/t Ag, 4.0% Pb, 3.8% Zn, 0.1% Cu |
| inc. WMDD6400W1 | 11.8m from 426m | 13.2% | 366g/t | 115g/t Ag, 5.0% Pb, 4.8% Zn, 0.2% Cu |
| inc. WMDD6400W1 | 5.4m from 432.4m | 19.5% | 540g/t | 173g/t Ag, 7.9% Pb, 6.5% Zn, 0.3% Cu |
| WMDD6391W1 | 14.1m from 394.8m | 9.4% | 261g/t | 36g/t Ag, 3.2% Pb, 5.4% Zn, 0.2% Cu |
| WMDD6391W1 | 11.1m from 420m | 9.0% | 248g/t | 40g/t Ag, 3.1% Pb, 4.9% Zn, 0.1% Cu |
| WMDD6391 (prior) | 25.8m from 415.1m | 11.7% | 323g/t | 39g/t Ag, 2.3% Pb, 7.9% Zn, 0.2% Cu, 0.1g/t Au |
ZnEq/AgEq metal price and recovery assumptions per company equation; gold results not yet received.
The company stated in its announcement that the continued stunning results confirm a major new discovery at the Rasp Mine and are driving a full reinterpretation of the previous understanding of mineralisation within the Centenary Zone.
When big ASX news breaks, our subscribers know first
The engineering breakthrough behind the discovery
Drilling below the Globe-Vauxhall Shear
This drilling program represents the first ever targeted drilling below the Globe-Vauxhall Shear at the Rasp Mine. Historically, no company has successfully drilled through the Shear without material distortion of the drill bit trajectory. This resulted in inaccurate drilling and the abandonment of many holes. As a result, only 24 holes have ever been drilled into the Centenary Zone, with the majority being 1980s surface drilling.
BHM’s targeted drilling was enabled through an innovative approach:
- A large-diameter hole is drilled through the Shear and cased.
- Smaller “daughter” holes are then drilled through the casing into the Centenary Zone without disruption.
- Platforms off lower levels of the Western Mineralisation enable close-proximity drilling below the Shear.
Analysis of the drill core continues to indicate a strong similarity to the Main Lode ore body. The presence of Hedenbergite and Tetrahedrite within the core demonstrates significant differences in Centenary geology compared to the adjacent Western Mineralisation. Centenary is assessed to more closely resemble the high-grade Main Lode mineralisation rather than the Western Mineralisation.
Understanding Centenary — the deposit in context
What is the Centenary Zone?
The Centenary Zone was discovered in 1983 — a century after the discovery of Rasp’s Main Lode. It sits structurally below the Globe-Vauxhall Shear, which distinguishes it from the shallower Main Lode and Western Mineralisation ore bodies that have historically fed the Rasp operations.
Despite more than four decades since discovery, Centenary remains one of the least-drilled parts of the Rasp system. The current Inferred MRE stands at 4.8Mt @ 9.2% ZnEq, 255g/t AgEq (39g/t Ag, 2.4% Pb, 6.0% Zn).
Geometrically, Centenary is defined by an approximate 1,600m strike length and an approximate vertical plunge extending over 280m. Mineralisation remains open both at depth and along strike in multiple directions.
Why proximity matters to investors
Centenary sits approximately 200–300m from current operations in the Western Mineralisation, placing it within practical reach of existing declines, ventilation, and haulage infrastructure. This proximity positions Centenary as a brownfields development pathway with materially lower capital intensity than a standalone project.
The discovery represents a potential high-grade, bulk tonnage feed for BHM’s 750,000tpa operation and could underpin a plant expansion opportunity in the medium term. For investors, this translates to potential growth without the capital demands of greenfields development.
The next major ASX story will hit our subscribers first
What’s next — pending assays and the roadmap to an MRE upgrade
The Company’s latest drill hole, WMDD6389A, is located approximately halfway between WMDD6391W1 and WMDD6400W1. Based on visual inspection only, the hole has intersected a zone of mineralisation up to 35m thick, with grades expected in line with the two assayed holes. Assays for WMDD6389A are pending and expected within 4–6 weeks.
Cautionary Statement: Visual estimates of mineral abundance are preliminary and should not be considered a proxy or substitute for laboratory analysis. They do not determine metal grades and may not identify impurities or deleterious physical properties relevant to valuation. Samples from WMDD6389A have been submitted to the laboratory for analysis.
Roadmap:
- Additional drilling is underway to continue defining the new discovery and delineate an Exploration Target.
- The Company is expediting reinterpretation of historic Centenary drilling.
- A Centenary Zone MRE and Rasp Mine upgrade is targeted for Q4 CY26.
- Further assay results are expected in the coming weeks.
For investors, the Q4 CY26 MRE upgrade represents the next major catalyst to watch.
Don’t Miss the Next ASX Mining Discovery
Join 30,000+ investors getting FREE breaking ASX mining news delivered to your inbox within minutes of release, complete with in-depth analysis. Click the “Free Alerts” button at Discovery Alert to start receiving real-time alerts the moment market-moving announcements hit the ASX.