Pilbara Gold has launched its largest-ever drilling program at Mt York, aiming to build on its 2.1 million ounce gold resource with extensive extensional drilling and a new geophysical survey.
- 5,680m diamond drilling completed with initial results due in July
- Largest 50,000m drill program targets depth extensions along 4.2km BIF
- Visual signs of high-grade gold indicators at Main Hill Extension
- Four holes at Gilt Dragon show encouraging hydrothermal alteration
- Airborne electromagnetic survey planned to identify new sulphide targets
Record Drilling Pushes Mt York Resource Boundaries
Pilbara Gold (ASX:PGL) is ramping up exploration at its flagship Mt York Gold Project in Western Australia with a +50,000 metre drilling campaign; the largest in the company’s history. Since early April, the team has completed 5,680 metres of diamond drilling across multiple prospects, including Main Hill Extension, Gossan Hill, Breccia Hill, and Gilt Dragon, with initial assay results expected in July.
The program focuses heavily on extensional drilling below the current 2.1 million ounce resource, hosted within a 4.2-kilometre banded iron formation (BIF). Previous work in 2025 only tested the upper 100 metres of the deposit, leaving the deeper potential largely untested. Pit optimisations earlier this year highlighted the lack of data constraining resources at depth, making this campaign critical to expanding the Mineral Resource Estimate (MRE).
Geological Signs Point to High-Grade Potential
Visual logging from the Main Hill Extension drilling has identified moderate-to-strong arsenopyrite development, a key indicator mineral for high-grade gold mineralisation in this region. Structural analysis has also revealed north-south trending cross faults offsetting mineralised BIF units by up to 50 metres, providing new insights for targeting future drill holes.
Meanwhile, four diamond holes drilled at the Gilt Dragon prospect, located 3 kilometres southeast of Mt York, intercepted zones of chalcopyrite and chalcocite within quartz-carbonate veins. This hydrothermal alteration suggests the presence of sulphide-rich gold systems, although assay results are still pending.
Expanding Drilling Capacity and Regional Survey Plans
Currently, three diamond rigs operate on double shifts, with two additional reverse circulation (RC) rigs expected to join in June. The RC rigs will mainly drill precollars for deeper diamond holes across the main prospects, accelerating the campaign’s pace.
Complementing the drilling, Pilbara Gold is preparing an airborne electro-magnetic (AEM) survey over approximately 200 square kilometres of the Greater Mt York area. This survey aims to detect buried sulphide-bearing gold deposits within the BIF-dominant stratigraphy, leveraging recent petro-physical studies that identified chargeable and conductive sulphide signatures associated with mineralised core samples.
The AEM survey, planned for July or August, could uncover new targets beyond the current resource footprint, adding a regional dimension to the company’s growth strategy.
Resource Growth to Feed Prefeasibility Study
The expanded drilling program and upcoming geophysical data will feed into an updated MRE and underpin Pilbara Gold’s Prefeasibility Study (PFS). The company aims to refine metallurgical, geotechnical, and mine scheduling parameters as it advances Mt York towards development.
With the 2.1 million ounce base resource already demonstrating robust open-pit potential using a A$5,500/oz gold price, the focus now is on extending mineralisation at depth and upgrading inferred resources to indicated categories. This work builds on a 50% resource increase achieved in 2025 following 27,000 metres of drilling, supported by a solid cash position and recent mining lease grant that reduces development risk.
Bottom Line?
Pilbara Gold’s aggressive drilling and geophysical survey at Mt York set the stage for a potential resource upgrade that could reshape the project’s development trajectory.
Questions in the middle?
- Will July’s initial drilling results confirm high-grade extensions at depth?
- How effectively will the airborne EM survey identify new sulphide-bearing targets?
- What impact will resource growth have on the timing and economics of the Prefeasibility Study?