JOHANNESBURG (miningweekly.com) – Mponeng Gold Mine – the world’s deepest mine at a depth of 4 km with extension towards 4.22 km planned – has delivered another strong quarter, Harmony reported in its operational update for the three months ended September 30.

In the first quarter of Harmony's financial year 2027 (FY27), the recovered grade at Mponeng, near Carletonville in South Africa’s Gauteng province, increased by 10% to 11.55 grams of gold per ton (g/t) and production was steady at 2 725 kg (87 611 oz).

The overall average gold price received in the quarter was a 17%-higher R2 123 588/kg ($4 057/oz).  

Gold all-in sustaining costs were at the lower end of guidance, the business continued to generate strong cash flows and the Johannesburg Stock Exchange-listed gold and copper mining company remained confident of meeting FY27 guidance for production, cost and grade.

Gold revenue increased by 3% to R22.3-billion and copper revenue hit the R1 280-million mark on an average received copper price of $6.44/lb.

In line with guidance, overall group gold production was a 12%-lower 10 661 kg (342 758 oz) and 7 077 t of copper were produced. Comparable reporting period did not include Harmony’s CSA copper mine.

“Five years ago, Harmony was predominantly a South African gold producer. Today, we are a higher-quality gold and copper producer operating in South Africa, Papua New Guinea and Australia, with a clear growth trajectory,” Harmony CEO Beyers Nel pointed out in a release to Mining Weekly.

“Margins at our gold operations remain robust. CSA is now an established part of the group, contributing copper revenue alongside our gold,” added Beyers, while pointing out that the Moab Khotsong gold mine, near the Orkney and Klerksdorp and straddling the North West and Free State provinces, is moving through its planned gold ore gap while the  Eva copper project in Australia remains has passed another approval milestone on its path to production.

Production at Tshepong North gold mine increased by 23% to 1 020 kg (32 794oz) driven by higher tonnes milled and higher grades.

Harmony has attributable gold mineral reserves of 27.4-million ounces and copper mineral reserves of four-million tons.

Having completed the first quarter of FY27, group full-year gold production of 1 400 000 oz to 1 500 000 oz and 28 000 t to 30 000 t of copper are being guided.

Mponeng's life-extension programme continues to advance access to the Ventersdorp contact reef and carbon leader reef below existing infrastructure alongside the Tau Tona pillar extraction project. Together, these will access about 3.6-million ounces in reserves.

The Moab Khotsong’s Zaaiplaats extension provides access to about 3.8-milloion ounces in high-grade gold resource below existing infrastructure.

Tshepong's life-extension project had a positive first quarter, with development ahead of plan, costs aligned with the overall estimate and initial construction milestones on track. The project accesses 1.1-million ounces  in reserves and extends the life of the mine to 15 years while leveraging existing infrastructure.

Quarterly development of Doornkop gold mine’s 207/212 life-was ahead of plan and ventilation and electrical infrastructure milestones completed. The 207/212 project is designed to replace production tonnes from existing levels and accesses 1.3-million ounces in mineral reserves. This project includes additional exploration drilling to increase the resources available for mining.

At Mine Waste Solutions surface mining operation, the Mispah 1 pump station was commissioned  enablingreclamation of the 71-million tonne Mispah 1 tailings facility.

On the renewable energy front, Harmony’s  Sungazer 2 is progressing through phased energisation and further solar and battery-storage projects are advancing through development and procurement. The programme is aimed at increasing renewable-energy usage and reducing reliance on grid electricity across the South African portfolio.

In Australasia, the Stage 9 life-of-mine extension at Hidden Valley is progressing through feasibility study and early works phases, with the potential to extend mine life by six years. At CSA copper, the capital ventilation project continues to advance, with progress made on access development and the project delivery approach refined to support efficient execution. At Wafi Golpu, discussions between Harmony, Newmont and the Papua New Guinea government to secure the special mining lease are continuing.

EXPLORATION

Harmony's exploration focuses on growing and upgrading the mineral endowment it already owns, close to existing or planned infrastructure. This is a lower-cost, lower-risk path to mineral reserve growth and longer mine lives. This quarter, drilling returned high-quality results across both regions.

Exploration drilling across our South African operations continued to deliver encouraging results, increasing geological confidence and supporting mine-life extension. Strong drilling outcomes at Mponeng and encouraging results across several other operations reinforce the value embedded within our existing mineral endowment.

With much of this exploration located close to established mining infrastructure, the programme provides a capital-efficient pathway to bring additional ounces into

mine plans, supporting the long-term sustainability and quality of Harmony’s South African portfolio.

In Australia, more than 23 500 m of drilling was completed during the quarter across Harmony's Australasian copper and gold portfolio. Surface drilling at CSA ramped up to three rigs. Regional exploration also progressed, including completion of an airborne magnetic and radiometric survey to support ongoing target generation.

Resource-conversion drilling at Eva Copper continued along the Blackard-Legend trend, while first-pass drilling at Ivy Ann North identified a potential new zone of copper mineralisation just north of the existing deposit, with laboratory assays pending.

At Wafi-Golpu, drilling is targeting a potential continuation of the gold mineralisation of the Wafi Link Zone below the Reid Thrust. Zones of sulphide mineralisation were intersected, with results from the principal target zone pending.