Hillgrove Resources (ASX:HGO) has unveiled a significant increase to the copper-gold resource at its Kanmantoo mine in South Australia, along with a maiden ore reserve estimate.
Located roughly 55km from Adelaide, the mine operated as a series of open pits from 2010 to 2020, producing some 137,000 tonnes of copper and more than 55,000 ounces of gold. The project is fully permitted and includes a 3.6-million-tonne processing plant as well as a tailing storage facility with around 7 million tonnes of capacity.
Operations at the mine restarted in May 2023 with underground mining, and first copper was produced in February this year.
According to a resource estimate published in 2022, the Kanmantoo mine hosted 6.4 million tonnes grading 1.09% copper and 0.12 grams per tonne (g/t) gold, representing 69,600 tonnes of contained copper.
The new estimate, however, outlines a much larger resource measuring 19.3 million tonnes at 0.77% copper and 0.14g/t gold, representing 150,000 tonnes of contained copper and 82,000 ounces of gold.
That translates to an increase of 96% and 138% to the copper and gold resources, respectively.
Notably, the updated resource includes the addition of the Emily Star and North Kavanagh deposits, which together accounted for roughly 2.9 million tonnes.
Hillgrove says a review of “economic factors” and copper price assumptions resulted in a lower cut-off grade, which led to an increase of 6.8 million tonnes.
“When combined with the 96% increase in contained copper in the mineral resources, it is clear that there is a strong geological potential for the conversion of mineral resources to ore reserves, which will extend the mine life at Kanmantoo,” Hillgrove CEO Bob Fulker says.
“The goal next year is to continue the (drilling) program to convert additional mineral resources into ore reserves. Pleasingly, we are finding the grade improves as we improve the geological classification. Our focus continues to be on reliable delivery, building cash, and earning the right to grow. We remain on track in these areas.”
The updated resource also came with a maiden ore reserve for Kanmantoo measuring 2.8 million tonnes at 0.91% copper and 0.15g/t gold for 26,000 tonnes of copper and 14,000 ounces of gold.
Shares in Hillgrove were up 7.2% this morning to $0.067 as of 11:08am AEDT.
Write to Oliver Gray at Mining.com.au
Images: Hillgrove Resources
