Brightstar Resources has nearly doubled the Two Mile Hill-Shillington Mineral Resource to 1.45 million ounces, with the Indicated component rising 177% to 526,000 ounces. The result lifts the broader Sandstone Gold Project to 3.6Moz, while assays from deeper drilling could provide another resource catalyst later in 2026.
- Two Mile Hill-Shillington MRE rises 98% to 1.45Moz at 1.8g/t gold
- Indicated Resources increase 177% to 526koz at 1.6g/t
- Sandstone Gold Project reaches 3.6Moz and Brightstar Group reaches 5.2Moz
- Deeper Shirvington drilling intersected 53 visible-gold occurrences, with assays pending
- Updated resource to feed underground studies and the Sandstone PFS
Two Mile Hill Resource Reaches 1.45Moz
Brightstar Resources Limited (ASX:BTR) has turned Two Mile Hill into a substantially larger proposition, lifting the combined Two Mile Hill-Shillington Mineral Resource Estimate by 98% to 1.45 million ounces of gold at 1.8g/t. The increase came from infill and depth-extension drilling, with the company reporting a discovery cost of $6 per ounce for the 0.7Moz added.
The more important shift for project studies is the 177% increase in Indicated Resources to 10.4 million tonnes at 1.6g/t for 526,000 ounces. The remaining 920,000 ounces are Inferred, a category that carries lower geological confidence and cannot yet be treated as an Ore Reserve. No Measured Resource is reported in the updated table.
Deep Tonalite Supports Underground Case
Two Mile Hill now contains 1.36Moz, including 1.26Moz assigned to the underground resource, while Shillington contributes 86,000 ounces. The resource is concentrated in a tonalite body that widens significantly at depth: Brightstar says its interpreted width reaches about 400 metres around the 100mRL, compared with an average 50m to 80m higher in the system.
Contained ounces peak at roughly 5,900 ounces per vertical metre about 595 metres below surface, close to the base of the current model. That geometry is relevant to the company’s ongoing underground mining studies, although the resource has been reported using a 0.73g/t cut-off below the open-pit zone and still requires economic evaluation through the Sandstone pre-feasibility study.
Shirvington Assays Remain the Next Catalyst
The most obvious source of further upside has not yet entered the estimate. A roughly 3,800-metre diamond drilling program targeting the deeper Shirvington Zone has produced 53 logged occurrences of visible gold in its first two reported holes, with assays still pending. Four deep holes have extended drilling about 250 metres below the updated MRE, and two additional holes are nearing completion.
Assays incorporated into this update also returned broad, downhole intercepts of 112.6 metres at 1.02g/t gold and 172.5 metres at 1.00g/t. Higher-grade sections included 19.6 metres at 2.42g/t, including 0.4 metres at 55.2g/t. These are downhole lengths rather than confirmed true widths, so the eventual mining significance will depend on the geometry, continuity and economic treatment of the mineralisation.
Sandstone Scale Expands Before PFS
The Two Mile Hill upgrade takes the Sandstone Gold Project to 79 million tonnes at 1.4g/t for 3.6Moz, including 1.5Moz in the Indicated category. Brightstar’s total group resource now stands at about 5.2Moz. Mining studies are continuing on the new Two Mile Hill estimate ahead of the Sandstone PFS, which the company expects to deliver later this year.
Metallurgical work on fresh tonalite composites produced overall recoveries of 92.0% to 97.8% at 24 hours, with high gravity-recoverable gold in two master composites. However, the deeper tonalite extensions added by this resource update were not represented in those testwork composites. That leaves the PFS with a larger geological base, but also a specific technical question: how closely will the newly defined deep material behave in processing?
Bottom Line?
The resource milestone strengthens the Sandstone development case, but the next value test lies in converting ounces into reserves, mine designs and a credible PFS while deeper Shirvington assays remain outstanding.
Questions in the middle?
- Will the pending Shirvington assays add ounces at grades and widths sufficient to support another MRE upgrade?
- How much of the 920koz Inferred Resource can move into Indicated Resources or eventually Ore Reserves?
- Will metallurgical results from deeper tonalite match the recoveries recorded in the existing fresh-rock composites?