Pantoro Gold Ltd (ASX:PNR, OTC:PNTOF, FRA:RKN) has returned a series of high-grade gold intercepts from underground drilling at the Butterfly area within the Mainfield mining centre at its Norseman Gold Project in Western Australia.
The results come from drilling undertaken from the Bullen Decline, where the company is targeting extensions of the historic Mararoa Reef system — an area that has already produced an estimated 1.4 million ounces of gold.
Pantoro said the results highlight the strong exploration potential that remains across the Mainfield, with the Butterfly zone emerging as a priority target for further drilling and potential future mining development.
Isometric view of Mainfield Reefs highlighting Butterfly.
High-grade results from underground drilling
Drilling completed to date has returned multiple high-grade intercepts, including:
- 1.5 metres at 81.23 g/t gold, including 0.5 metres at 223.65 g/t
- 1.7 metres at 34.35 g/t gold, including 0.36 metres at 143.02 g/t
- 1.1 metres at 26.88 g/t gold, including 0.72 metres at 40.35 g/t
- 0.54 metres at 58.76 g/t gold
- 0.6 metres at 58.96 g/t gold, including 0.3 metres at 103.75 g/t
BFDD26-012 – 1.5m @ 81.23g/t.
BFDD26-008 – 1.7m @ 34.35g/t.
Pantoro noted that the mineralisation sits just 70 metres east of the recently developed Butterfly decline, allowing relatively straightforward access should mining proceed.
Known mineralisation in the Butterfly zone also extends about 1.5 kilometres to the south and remains open at depth, suggesting scope for further resource growth as drilling continues.
Exploration decline positions area for potential mining
Managing director Paul Cmrlec said the results reinforce the scale of opportunity still present within the Mainfield system.
“While the Mararoa Reef has been extensively mined in the upper levels historically, the current drilling is targeting unmined extensions which remain open along strike and at depth,” Cmrlec said. “Butterfly is a priority area, and ongoing drilling is aimed at defining additional resources.”
He added that Pantoro has already developed a dedicated exploration decline to position the area for potential rapid transition into production once sufficient drilling density is achieved.
Cmrlec noted that the Butterfly zone represents a separate opportunity to the O’Briens/Crown South area, which Pantoro recently identified as the next underground production area at Norseman, “highlighting the scale of the opportunity that remains across the mainfiled”.
Expanding exploration across the Mainfield
Pantoro’s current program includes an initial 26-hole underground diamond drilling campaign designed to test extensions of mineralisation beneath historic workings in the Butterfly area.
Based on the strong early results, the company expects the program to be significantly expanded to provide sufficient drill coverage to support the potential development of a second independent mining area within the Mainfield.
The Mainfield mining centre, located adjacent to the town of Norseman, has been a major source of gold production since the discovery of the district in 1894 and has produced about 3 million ounces historically.
Long view of results received to date.
Norseman growth strategy
Pantoro is focused on unlocking the full potential of its 100%-owned Norseman Gold Project, located at the southern end of the Norseman–Wiluna greenstone belt in Western Australia.
The project currently hosts 4.6 million ounces of gold in mineral resources and 859,000 ounces in ore reserves.
Pantoro completed construction of a 1.2 million tonnes per annum processing plant in 2022 and is progressing both open pit and underground mining activities across the project.
Under its growth strategy announced in mid-2024, the company aims to expand underground mining operations at Norseman, initially targeting annual production of around 100,000 ounces with longer-term ambitions to grow output beyond 200,000 ounces per year.
The growth strategy set for Norseman at the commencement of drilling in September 2024.