ActivEX Lifts Mt Hogan Gold Resource 30% to 403,000oz Despite Old Mine Depletion
Key Takeaways
- ActivEX's Mt Hogan resource has grown 30% to 403,000 oz of contained gold (9.8 Mt at 1.28g/t Au), a 93,000 oz gain against the AHD-cited June 2025 estimate.
- The increase came after depleting for 1992–1994 mining, which produced 67,700 oz, so the growth is net of past production.
- The drill database grew from 74 to 142 holes (13,717m), driven by a 52-hole, 5,091m RC program completed in November 2025.
- The resource remains Inferred, capped by nuggety gold continuity, and untested coarse-gold recovery is the main hurdle to an upgrade.
- ActivEX holds 20.95% of the project, and the announcement gives no timelines or funding for the metallurgical and twin-hole work that would lift confidence.
Mt Hogan resource lifts 30% to 403,000 ounces
A larger gold inventory has been declared at the Mt Hogan Gold Project, and it arrives even after the old mine workings were subtracted. ActivEX (ASX: AIV) reported a JORC-compliant Inferred Mineral Resource Estimate of 9.8 Mt @ 1.28g/t Au for 403,000 oz of contained gold at a 0.3g/t Au cut-off, effective 25 August 2026, completed by AHD Resources.
ActivEX holds 20.95% equity in the project, which is a Joint Venture with Gilberton Gold Pty Ltd, the Operator. As project operators, Gilberton Gold gave permission for the report to be released to the market.
The previous Maiden Resource Estimate was reported to the market on 21 July 2025. The AHD report puts the June 2025 estimate (prepared by Auspin Exploration and Drilling Pty Ltd) at 310,000 oz, and that is the figure used in the comparison below (the announcement body cites 301,000 oz). Against it, contained gold rose by 93,000 oz, or 30%.
| Estimate | Tonnes (Mt) | Grade (g/t Au) | Contained Au (oz) | Change |
|---|---|---|---|---|
| June 2025 (Auspin) | **8.5** | **1.13** | **310,000** | n/a |
| August 2026 (AHD) | **9.8** | **1.28** | **403,000** | n/a |
| Change | **+15%** | **+13%** | **+30%** | **+93,000 oz** |
The gains came notwithstanding depletion for historical mining. In plain terms, the ounces mined in the early 1990s have been removed from the count, and the total still grew. The AHD report describes this as the first estimate for the deposit depleted for the 1992–1994 production.
Management view
Managing Director Mark Derriman linked the result to the project’s longer-term direction, and credited the operator and the wider district.
Mark Derriman, Managing Director
“The increase in the Inferred Mineral Resource Estimate to 403,000 ounces of contained gold marks the continued evolution of the Mt Hogan Gold Project which hopefully one day leads back to operational status…”
He added that “The professionalism and drive of Gilberton Gold have been crucial to the success of the Mt Hogan Gold Project…” and said the resource area is “a small part of an 8km gold mineralised trend along the southern margin of the Mt Hogan Granite.” He also pointed to Josephine and Comstock, two other historic gold mining centres in the Gilberton Gold Project that have been lightly explored.
When big ASX news breaks, our subscribers know first
What drove the increase?
A further RC (reverse circulation) drilling program was completed in November 2025. It comprised 52 holes for 5,091m as described in the announcement, and the AHD report credits it, together with a revised domain interpretation, for extending and infilling the vein domains.
The estimate rests on a validated database of 142 drill holes for 13,717m, up from 74 holes behind the June 2025 figure. Mineralisation is interpreted as 44 vein domains, of which 41 are estimated.
The technical basis, as reported:
- Grades estimated by Ordinary Kriging in Leapfrog Edge, using a single normalised variogram model and hard domain boundaries
- Extreme grades controlled by outlier restriction rather than top cutting, in recognition of the deposit’s coarse gold character
- Block and composite grades agreeing within 4%
- Model volume reconciling to the wireframes within 0.01%
- A single bulk density of 2.70g/cc applied
Validation supports the estimate at a global, whole-of-deposit scale. For investors, the caveat matters: local block estimates are not suitable for detailed mine planning, grade control or short-term forecasting.
Mt Hogan’s mining history and why it matters
An Inferred Mineral Resource is the lowest-confidence category under the JORC Code. It means tonnes and grade are inferred from limited data, and it is an early stage that further work seeks to upgrade.
The announcement says the estimate is capped at Inferred by the pure-nugget grade continuity. Gold in a “nuggety” deposit occurs in coarse, erratic pieces, so grades can jump sharply between nearby samples, and continuity between drill holes is an assumption rather than something the data demonstrates. No part of the estimate satisfies the requirements of an Indicated Mineral Resource.
The deposit has real production behind it. Eltin Minerals mined Mt Hogan from 1992 to 1994, producing 67,700 oz from 405,000t at 5.2–5.5g/t. The announcement describes Mt Hogan as the largest historical gold producer in the Gilberton district, at 74,930oz.
Reasonable prospects for eventual economic extraction are supported at scoping-study level. The Mt Hogan Scoping Study demonstrated positive open-pit economics at A$4,500/oz with calculated cut-off grades of 0.33–0.39g/t Au. The study is based on the 2023 exploration-target model with assumed metallurgical recoveries, so it is an early-stage guide rather than a mine plan.
Upside is also flagged:
- Mineralisation remains open along strike and down dip in most domains
- Drilling extends only to approximately 220m below surface
- Silver (median Ag:Au 3.6) is unestimated and described as potential by-product upside subject to testwork
The next major ASX story will hit our subscribers first
Next steps to lift confidence
The recommended operational program to support an improved Mineral Resource Estimate is set out in priority order:
- Metallurgical testwork, heterogeneity and sampling testwork, and QAQC re-establishment for project compliance
- Twin-hole drilling of 2–3 RC holes, geotechnical and recovery logging, and a modern survey of historic workings
- Routine core and chip photography and a systematic density measurement program
AHD notes that the metallurgical and sampling testwork have direct impacts on the economic assumptions and the reliability of any future higher-confidence estimate. That makes the first item the one to watch, since recovery of coarse gold is untested.
The announcement does not disclose timelines or funding for this work.
The resource area is a small part of the 8km mineralised trend along the southern margin of the Mt Hogan Granite, with Josephine and Comstock lightly explored. For shareholders, the message is that the Inferred label is a starting point, and the next phase of testwork and drilling is what determines whether confidence can be lifted.
Don’t Miss the Next ASX Gold Breakout
Join 30,000+ investors getting FREE breaking ASX gold news delivered to their inbox within minutes of release, complete with in-depth analysis and the full announcement. Click the “Free Alerts” button at Big News Blast to stay ahead of the market the moment news breaks.