Hillgrove Resources (ASX:HGO) has approved development of Emily Star as the third underground mining front at its Kanmantoo Copper Mine in South Australia.
The development is expected to cost between $20 million and $22 million, in addition to $2.9 million already spent on drilling and early works. Hillgrove plans to spend $6.5 million to $7.5 million during the second half of 2026.
Stoping is scheduled to begin in H2 2027 following decline development and the establishment of level access. The planned stopes will average approximately 35,000 tonnes.
Drilling across the upper levels of Emily Star confirmed geological continuity and returned grades consistent with the existing block model. Hillgrove says geotechnical work identified variable ground conditions typical of Kanmantoo, but no risks that would prevent development or future stoping.
CEO Bob Fulker says the drilling has increased the company’s confidence in proceeding with the development.
“Emily Star provides an additional mining front, strengthens operational flexibility, and supports sustained copper production over the life of mine,” Fulker says.
Once Emily Star enters production, Hillgrove expects it to replace part of the lower-level output from its Kavanagh production while supporting a 2 million tonne (Mt) per annum mining rate at Kanmantoo.
The company says increased plant throughput would spread fixed costs across a larger production base, reducing unit all-in sustaining costs.
Hillgrove has increased its 2026 major capital guidance from $8 million–10 million to $15 million–17 million to account for Emily Star and phase one work on the Mutooroo Prefeasibility Study. It says the revised program will be funded from operating cash flow.
Development will initially proceed under Kanmantoo’s existing program for environment protection and rehabilitation. Hillgrove plans to submit an updated program later this year, with approval expected before stoping begins.
Emily Star currently hosts an inferred mineral resource estimate of 2.6Mt @ 0.77% copper and 0.08 grams per tonne gold. An updated estimate will form part of Hillgrove’s December-quarter mineral resources and ore reserves update.
Write to France Pinzon at Mining.com.au
Images: Hillgrove Resources
