Pantoro Gold Ltd (ASX:PNR, OTC:PNTOD) has reported multiple high-grade intercepts from ongoing diamond drilling at the O2 orebody within its OK Underground Mine, part of the 100%-owned Norseman Gold Project in Western Australia.
Key intercepts include:
- 5.94 metres at 34.47 g/t from 102.8 metres, including 0.3 metres at 209.68 g/t
- 0.32 metres at 349.96 g/t from 109.44 metres
- 5.69 metres at 75.99 g/t from 174.31 metres, including 0.31 metres at 969.81 g/t
- 6.3 metres at 10.11 g/t from 200.2 metres
- 1.06 metres at 26.71 g/t from 138.13 metres
The drilling has confirmed the continuity of mineralisation at depth and along strike, particularly on the northwestern end of the O2 lode, with the company expecting OK to provide a baseload of high-grade feed long into the future.
“These results confirm ongoing continuity of mineralisation at depth in the OK Underground Mine ore system. With drilling to be ongoing at the mine for the foreseeable future, Pantoro Gold is confident that the OK Underground Mine will provide a baseload of high-grade mill feed long into the future,” PNR managing director Paul Cmrlec said.
Pantoro has four full-time underground diamond drill rigs operating across its three underground mines at Norseman. The latest campaign at OK targets infill and extensional drilling of the Star of Erin and O2 lodes. Notably, hole OKDD25_100 intersected 6.3 metres at 10.11 g/t gold from 200.2 metres, 160 metres below current development.
Drilling has also identified potential for a mineralised linking structure between two strong ore domains at the northwestern end of the lode, enhancing exploration upside. Additional high-grade intersections at depth below the current Star of Erin Mineral Resource suggest continued growth potential from ongoing drilling.
Historical performance and geology of OK Underground Mine
The OK Underground Mine, situated roughly two kilometres south of the 1.2 million tonnes per annum Norseman Processing Plant, continues to deliver high-grade gold production. Since resuming operations in May 2022 via the OK decline, the mine has yielded 70,718 ounces of gold at an average grade of 5.19 grams per tonne (g/t) gold.
OK and Star of Erin currently host a combined Mineral Resource of 457,000 tonnes at 14.86 g/t gold for 218,000 ounces, with scope for further growth through ongoing drilling.
The mined reefs at OK strike predominantly northeast and east, dipping sub-vertically. Initially mined in the 1930s, the site was dormant until 1980 when Central Norseman Gold Corporation (CNGC) reopened the shaft to extract remnant ore from the OK Main Reef. Subsequent underground drilling of the east-striking tensional Main Reef led to the discovery of the northwestern-striking O2 Reef.
Since 2022, the Star of Erin reef has been a key development focus. Gold mineralisation in this zone is hosted in shear-vein systems, with free-milling gold typically found in a laminated quartz vein averaging 0.3 metres wide and surrounded by up to two metres of biotite alteration.
The OK reefs are among the most nuggety within the Norseman region, with historical grades averaging 9.1 g/t gold. Current mechanised production has achieved mill-reconciled grades of approximately 7 g/t gold.
Recent drilling at OK has returned multiple high-grade intercepts, including:
- 10.15 metres at 44.39 g/t gold, including 4.08 metres at 106.53 g/t
- 2.72 metres at 139.08 g/t gold
- 3.94 metres at 101.71 g/t gold, including 0.47 metres at 836 g/t
- 1.63 metres at 13.32 g/t gold
- 2.86 metres at 10.2 g/t gold
- 0.96 metres at 63.65 g/t gold, including 0.6 metres at 100.35 g/t
- 1.6 metres at 41.68 g/t gold
- 1.25 metres at 12.66 g/t gold
- 0.7 metres at 89.83 g/t gold, including 0.27 metres at 231 g/t
- 0.41 metres at 200.42 g/t gold, including 0.2 metres at 408 g/t
Further drilling is ongoing to support resource growth and operational planning.
About the Norseman Gold Project
The Norseman Gold Project spans 800 square kilometres across the southern end of the Norseman-Wiluna greenstone belt. Pantoro has drilled over 300,000 metres since 2019, established a new 1.2 million tonnes per annum processing plant, and defined Ore Reserves of 895,000 ounces. The Total Mineral Resource stands at 4.7 million ounces of gold.
Pantoro’s growth strategy targets production expansion from 100,000 ounces to over 200,000 ounces annually. Up to 250,000 metres of drilling is planned for FY26, with underground development and resource growth central to the company’s forward outlook.