Greatland Resources has delivered a major upgrade to its Telfer gold-copper project in Western Australia, with the mineral resource growing 150% to 8.0 million ounces, adding 4.8 million ounces.
The update, based on around 134,000 metres of drilling completed during 2025, also saw the higher-confidence Measured and Indicated category surge 163% to 3.8 million ounces, a critical milestone as Greatland targets an updated Ore Reserve Estimate in the June 2026 quarter.
Much of the attention has been on Greatland’s Havieron project, but today’s resource upgrade puts Telfer on par with Havieron in terms of resource.
Combined with the unchanged Havieron resource, Greatland’s total gold-copper resource base now stands at 14.9 million ounces of gold and 645,000 tonnes of copper.
The West Dome Open Pit drove much of the growth, adding 2.8 million ounces to reach 4.9 million ounces, while the Main Dome Underground more than tripled to 2.2 million ounces.
A maiden resource of 0.6 million ounces was also declared for the West Dome Underground at an average grade of 2.30g/t, roughly three times the open-pit grade, highlighting the upside of greater underground utilisation.
Greatland has more than 100,000 metres of further drilling planned for the second half of its record FY26 programme, with a substantial campaign also lined up for FY27. The company said its focus is now shifting towards higher-grade opportunities, including the West Dome Underground and the Main Dome sub-level cave area.
The resource estimate uses conservative metal price assumptions of A$4,200 per ounce for gold and A$6.50 per pound for copper, against spot prices of roughly A$6,500 and A$8.00, respectively.
Greatland Gold shares were 6% higher at the time of writing in London.
“Telfer and Havieron’s combined resource of 550Mt @ 0.84g/t Au & 0.12% Cu for 14.9Moz Au & 645Kt Cu has the potential to underpin a multi-decade, world class mining hub. Our investment in significantly increased drilling has delivered substantial organic growth, with the overall Telfer resource growing by 150% to 8.0Moz, and the higher confidence Measured and Indicated component by 163% to 3.8Moz,” said Greatland Managing Director, Shaun Day.
“The growth includes a high-grade maiden resource at the West Dome Underground project, which shows significant potential for a new mining front at Telfer and remains the focus of ongoing drilling.
“This strong resource update has been delivered by Greatland’s dedicated technical team who have executed an accelerated and extensive Telfer drilling program since taking ownership in December 2024.
“The significant growth in Measured and Indicated Resources, particularly at the West Dome Open Pit, is very pleasing with this material being of adequate geological confidence to be evaluated as part of our upcoming Ore Reserve estimate, which remains targeted for the June 2026 quarter.
“The scale of Telfer’s resource demonstrates clear potential to fully utilise our low cost 20 million tonne per annum processing infrastructure well into the future. The technical team’s focus is now to advance our higher grade opportunities including the West Dome Underground and the potential to restart Main Dome Underground’s sub-level cave, which could augment our development of Havieron.”