Pantoro Gold Ltd (ASX:PNR, OTC:PNTOD) has reported a series of high-grade intersections from underground drilling at the Bullen Decline within the historic Mainfield mining centre at the Norseman Gold Project in Western Australia.
The results mark the first underground drill intercepts at Mainfield in two decades, highlighting the potential to expand Pantoro’s resource base and accelerate underground development at the 100%-owned project.
Isometric view of Mainfield Reefs.
High-grade hits across multiple reefs
Pantoro said drilling from the rehabilitated Bullen Decline had successfully intersected all targeted lodes — Crown South, Bullen West, Norseman and Esperanto — returning standout grades, including a peak intercept of 0.68 metres at 137.19 grams per tonne (g/t) gold.
Plan view of Crown South initial drilling.
Other notable results include:
- 1.13 metres at 12.36 g/t (including 0.36 metres at 27.63 g/t)
- 1.37 metres at 15.69 g/t (including 0.53 metres at 38.57 g/t)
- 1.64 metres at 11.79 g/t (including 0.3 metres at 44.31 g/t)
- 0.32 metres at 71.14 g/t
- 0.83 metres at 31.24 g/t
- 0.91 metres at 13.47 g/t
Core from Bullen West - Hole ID BWDD25_006.
The company also identified new mineralisation outside historically mined zones, including the bonanza-grade intersection near the O’Brien’s Reef zone, which hosts a Probable Ore Reserve of 129,000 tonnes at 5.0 g/t for 21,000 ounces.
Revival of a historic producer
Discovered in 1894, the Mainfield system was the cornerstone of Norseman’s gold production for more than a century, yielding around 3 million ounces from multiple reefs. The Bullen Reef alone produced about 500,000 ounces before operations ceased in 2013.
Pantoro’s latest program — the first phase of underground drilling from the Bullen Decline — is designed to confirm and extend mineralisation across several known structures, including Crown South, Norseman, Esperanto and Bullen West. Each reef has delivered encouraging results, with visible gold observed in several holes and extensions now being tested at depth.
Near-term development potential
Pantoro managing director Paul Cmrlec said the results validate the company’s decision to prioritise Mainfield as a near-term growth target.
“After an intensive period of rehabilitation in the Bullen Decline this year, it is exciting to see the diamond drill rigs turning out high-grade underground intercepts for the first time in 20 years,” Cmrlec said.
“These results confirm that extensive high-grade ore zones can be defined, developed and mined in the near term,” he added. “While our operating plan currently has new mine developments commencing during FY2027, we aim to fast-track development once we are confident in the definition of economically viable ore panels.”
Next steps
Pantoro will continue drilling across the Mainfield area to build resource confidence and prepare for underground development. Dewatering and rehabilitation of the Bullen Decline are ongoing, with new ore zones expected to transition into development once sufficient drill density is achieved.
The company’s Norseman Project currently hosts a total mineral resource of 4.6 million ounces of gold and ore reserves of 859,000 ounces. Pantoro aims to expand annual production beyond 200,000 ounces as part of its broader growth strategy.