178m at 0.70g/t Au Highlights Bull Oak’s Expansion Upside

Exploration Momentum at Sandstone Hub

Brightstar Resources Limited (ASX, BTR) has delivered a fresh wave of encouraging gold assay results from its extensive drilling campaign at the Sandstone Hub in Western Australia's East Murchison region. The latest data, including the final hole from the maiden reverse circulation (RC) program at the Bull Oak deposit, reinforces the deposit’s potential to underpin a large-scale open pit mining operation.

The Bull Oak deposit, hosted within a granodiorite intrusion, currently holds a mineral resource of approximately 90,000 ounces of gold at 1.1 grams per tonne. The recent drilling, comprising five extensional RC holes, has returned a standout intercept of 178 meters grading 0.70 grams per tonne gold, featuring narrow but very high-grade zones up to 20.5 grams per tonne. These results confirm the continuity of mineralisation beneath the existing resource and validate the previously announced exploration target, suggesting substantial upside.

High-Grade Lodes Within Bulk Mineralisation

What makes Bull Oak particularly compelling is the presence of multiple high-grade quartz reefs embedded within a broader halo of lower-grade gold mineralisation. This geological setting is classic for bulk-tonnage deposits amenable to open pit mining, offering both scale and grade. The recent assays include impressive narrow intercepts such as 1 meter at 20.5 grams per tonne and 1 meter at 13.7 grams per tonne, highlighting the potential for selective high-grade extraction alongside bulk mining.

Brightstar’s Managing Director, Alex Rovira, emphasised the significance of these findings, noting that Bull Oak could provide a substantial feed source for Sandstone’s mining operations. The deposit is one of several mineralised felsic intrusives within the so-called Bull Oak Camp, a promising area for future resource growth.

Early-Stage Promise at Sandstone North

Alongside Bull Oak, exploration at the Sandstone North prospect, located about 6 kilometers north of the town of Sandstone, has yielded encouraging results from an early-stage RC drilling program. Targeting mineralisation beneath historical workings, the drilling intersected consistent widths and grades, including intercepts such as 2 meters at 7.54 grams per tonne and 5 meters at 3.17 grams per tonne. While still in the preliminary phase, these results suggest genuine resource potential warranting further follow-up.

Broader Exploration and Development Outlook

Brightstar’s ongoing +80,000-meter drilling program across the Sandstone Hub aims to expand and upgrade the current 1.5 million ounce mineral resource. The company is also advancing drilling activities at its Laverton and Menzies hubs, with RC and diamond rigs actively deployed to accelerate resource definition. Notably, ore from Brightstar’s Laverton underground mines is currently processed under an ore purchase agreement with Genesis Minerals, providing a near-term production pathway.

With a pre-feasibility study targeted for the first half of 2026, Brightstar is methodically building its resource base and technical understanding to support future mining operations. The integration of historical data, modern drilling, and systematic exploration is positioning the company to unlock value across its Western Australian gold portfolio.