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The sale of South Africa's aluminium value chain assets to Alcoa Corporation of the US remains on track for completion in the June 2027 half-year, Johannesburg-, Sydney- and London-listed South32 reported in its September quarterly on Monday, October 19.

In the three months to September 30, aluminium production was largely unchanged as South Africa's Hillside Aluminium in KwaZulu-Natal continued to test nameplate capacity with a quarterly output of 179 000 t. South32's Brazil Aluminium is in ramp-up and as reported in March, South32's Mozal Aluminium is on care and maintenance.

As a global producer of materials across the aluminium value chain – taking in mining, refining and producing bauxite, alumina, and aluminium – Alcoa of Pennsylvania was on July 1 described by South32 COO Africa Noel Pillay as being well positioned to operate South Africa's Hillside Aluminium business into the future. This followed the signing by South32 of a binding conditional agreement to sell Hillside to the New York-listed Alcoa for up to $5.6-billion.

In addition to the Hillside aluminium smelter and South Africa's idled Bayside smelter, Alcoa, headed by president and CEO William (Bill) F Oplinger, will also acquire South32's interests in Boddington bauxite mine and the Worsley alumina refinery in Australia, as well as the Mineração Rio do Nortebauxite mine and the Alumar alumina refinery and aluminium smelter in Brazil.

Meanwhile, on the manganese front, South Africa's manganese output for the quarter was 528 000 wet metric tonnes following South Africa Manganese lifting underground productivity at the Wessels mine in South Africa's manganese-rich Kalahari basin, which is home to 80% of the world's manganese.

South32's South Africa Manganese is made up of two manganese mines, the opencast Mamatwan mine, which started operating more than half a century ago, and the underground Wessels mine, which followed a few years later. Wessels has vertical and incline shafts and uses the mechanised bord-and-pillar mining method, while Mamatwan applies the terrace mining method. The two form part of Hotazel Manganese Mines.

New South32 CEO Matt Daley spoke of achieving key development milestones for the company's copper and zinc growth projects.

Sierra Gorda, the opencast copper mine in the Antofagasta region of northern Chile, increased payable copper equivalent production by 11% on higher planned copper grades and paid a record quarterly distribution of $153-million. A fourth grinding line project at Sierra Gorda is expected to increase processing capacity by 25% and further increase the exposure to copper.

At Hermosa, in the Patagonia Mountains south-east of Tucson, Arizona, South32 continued construction of underground and surface infrastructure for the Taylor zinc/lead/silver project and completed the federal permitting process. Hermosa also has the zinc-/manganese/silver Clark oxide deposit, the copper/lead/zinc/silver Peake exploration target and the Flux prospect.

Hermosa provides the opportunity to leverage the underground mining and processing methods South32 has used at its Cannington operation in Queensland, Australia.

Net cash increased by $14-million to $297-million in the quarter and financial year 2027 production guidance remains unchanged, South32 stated in its release to Mining Weekly.

This audio is brought to you by Endress and Hauser, a global leader in process and laboratory measurement technology, offering a broad portfolio of instruments, solutions and services for industrial process measurement and automation.

Iron-ore major Fortescue has sold more than 40 t of copper concentrate cleaned using its new world-first arsenic removal technology, creating a solution for a complex problem facing the global copper industry.

The patented Toowong Process uses a low-temperature, low-pressure hydrometallurgical method to separate arsenic from copper concentrate.

Fortescue acquired the technology in 2022 and has been developing and testing it over the last four years at its Brisbane demonstration plant.

Across seven campaigns and more than 3 000 hours, the Toowong Process reduced arsenic levels in concentrates to below 0.3%, while also retaining more than 99.9% of the copper.

Arsenic has been a major barrier to unlocking new copper resources globally and its removal from copper ores has conventionally relied on roasting, an incredibly energy-intensive process. Roasting generates significant emissions, requires complex infrastructure and produces toxic water-soluble arsenic bearing gas and dust emissions that need to be controlled.

The Toowong Process is proving to be an economic alternative, with comparable capital and operating costs, improved output and reduced energy consumption and emissions.

The first 40 t of cleaned copper concentrate produced from Fortescue's Brisbane site contained less than 0.25% arsenic, reduced from feedstocks containing up to 7% of the contaminant.

This product has now been sold, demonstrating that the Toowong Process can produce marketable, commercially competitive copper concentrate from high-arsenic feedstocks.

"Technology and innovation are central to Fortescue's future growth. We look for problems others see as barriers and work out how to solve them.

"In the early days of iron-ore, Fortescue challenged the assumption that lower-grade deposits could not be developed competitively. The Toowong Process brings that same mindset to copper," says Fortescue growth and energy CEO Gus Pichot.

He adds that this technology has the potential to make high-arsenic deposits more economically viable, addressing major processing challenges and eliminating emissions at the same time.

"The world needs more copper to build renewable-energy projects and expand electricity networks and Fortescue's innovations will be key to unlocking the resources that can meet that demand," Pichot states, adding that the company will use this technology as it explores more copper deposits globally and make it available for its peers.

Global copper demand is forecast to grow more than 50% by 2050, reaching at least 50-million tonnes a year.

Existing clean ore bodies are being depleted to meet that demand, forcing copper producers to explore and develop more complex deposits that can contain higher levels of impurities, including arsenic.

Until now, arsenic has made some copper concentrates unmarketable, with smelters unwilling to accept product or imposing costly penalties that reduce value. High arsenic levels can also constrain mine plans if material must be blended, treated or excluded.

The Toowong Process has the potential to improve the saleability of copper concentrate - removing arsenic turns otherwise unmarketable concentrate into a product that can be sold. It also allows producers to optimise mine inventories, lower development costs, improve life-of-asset production and reduce environmental impacts.

Pichot explains that compared with roasting, the Toowong process uses less energy, generates lower emissions and captures arsenic in a stable, solid product.

Fortescue continues, meanwhile, to optimise the Toowong Process and advance its commercial engineering, with a focus on further reducing capital and operating costs.

This includes testing concentrate produced from Fortescue's Cañariaco copper project in P...

This audio is brought to you by Endress and Hauser, a global leader in process and laboratory measurement technology, offering a broad portfolio of instruments, solutions and services for industrial process measurement and automation.

The first copper and zinc production from Uppers at the reviving Prieska Copper Zinc Mine in South Africa's well-endowed Northern Cape is targeted for the end of next year, Orion Minerals reported on Monday, October 19, following the way for this being cleared by financing and offtake agreement finalisation.

The $40-million tranche A financing from Glencore is now unconditional and gthe first drawdown is expected by the end of this month, enabling key development contracts, site mobilisation and construction activities to progress.

Tranche B financing of $210-million remains conditional, with Orion continuing discussions with funding partners to secure the remaining financial required for the development of the Deeps Mine, also at Prieska.

Prieska's first phase will target early production from the shallower, higher-grade Uppers, with dewatering of historical underground workings progressing in parallel and the second phase the more extensive Deeps resource, as dewatering, shaft rehabilitation and infrastructure provision are completed.

Exploration will continue alongside development. Five extension targets have been identified at depth and are planned to be evaluated through underground drilling as access improves, providing further potential to expand the resource base and extend mine life.

Over the past year, work at Prieska has been focused on operational readiness, detailed engineering and transitioning the project from planning to executable work packages.

Torque Africa has been appointed to carry out the drilling programme, which is structured to support geotechnical and final mine design definition ahead of mining, while Enprotec has been selected to deliver the 20 000 t/m Uppers concentrator under a build-own-operate-transfer arrangement.

Also enabled by Tranche A funding is a start being made on the construction of an accommodation village.

Orion will continue to engage with existing and new funding partners to secure the remaining project financing required to proceed with development of the Deeps In parallel with commencing mobilisation of construction crews and equipment to site.

While finalising these agreements has been a lengthy and detailed process, our project and operations teams have used this time productively to advance engineering, finalise development plans, select key contractors and establish the systems and processes required for disciplined project execution.

"This puts us in a strong position to commence development activities, with a strong focus on safety, operational readiness, cost control and project governance.

"The world continues to require ever increasing volumes of new copper and zinc production to meet crucial energy transition goals and we look forward to bringing this important South African resource into production and delivering long-term benefits for our shareholders, employees and local communities," Orion CEO Tony Lennox stated in a release to Mining Weekly.

"We are pleased to assist Orion with financing for it to bring Prieska back to life and become South Africa's next copper producer," Glencore's Toby Spittle added.

The Prieska Copper Zinc Mine, located near Copperton, is on a volcanogenic massive sulphide deposit, which between 1971 and 1991 produced 430 000 t of copper and a million tons of zinc when previously operated by South Africa's now defunct Anglovaal.

In addition to the Prieska Copper Zinc Mine, the Johannesburg- and Sydney-listed Orion is Orion's progressing Okiep Copper Project, which also has a premier historical copper record in a district that produced more than two-million tons of copper over 150 years.

At Okiep, drilling results have confirmed ongoing high-grade Flat Mine East copper mineralisation, with intercepts of 7.88 m a...

Mining Weekly Editor Martin Creamer says Anglo American still sees huge opportunity in South Africa; he discusses Mineral Resources and Petroleum Minister Gwede Matashe wanting South Africans to rally to confront the high fuel price; and he unpacks the decrease of mining producti

This audio is brought to you by Endress and Hauser, a global leader in process and laboratory measurement technology, offering a broad portfolio of instruments, solutions and services for industrial process measurement and automation.

JSE-listed Copper 360 advises that the incline at the Rietberg underground mine, in the Northern Cape, has intersected copper sulphide mineralisation about 16 m before reaching the planned 300 Level (300L) elevation.

This is earlier than expected from the company's geological model and could represent a new mineralised body, it highlights.

Assays from bulk sampling of the intersection have returned representative grades ranging between 0.48% and 1.50% total copper.

The intersection was made on October 6, and management immediately followed up with geological mapping and sampling.

The mineralisation is hosted in the mafic rocks of the Koperberg Suite, with visible bornite and chalcopyrite.

The planned 400 to 300 Level incline has progressed through this intersection, exposing about 6 m of mineralised mafic rocks.

To obtain representative samples, two composite samples were collected from the stockpile of the mineralised material.

The samples were crushed to –10 mm, homogenised by coning and quartering and subsequently submitted for assay.

Samples were assayed at QLS Laboratory (unaccredited) in Springbok for total sulphide copper.

No acid-soluble analysis was done since no oxide copper minerals were observed and the intersection is far below the known oxide and transition zones, Copper 360 points out.

Quality control samples were included, and all returned results fell within acceptable industry limits.

The company explains that the earlier-than-expected intersection may indicate that the mineralisation extends beyond its currently modelled limits, or that a potential "offshoot" was intersected.

Some legacy borehole intersections (data) are available in proximity.

The company says it will test this through further mapping and face sampling and will update its geological model accordingly.

The intersection does not change the company's mine plan.

Copper 360 will continue to establish the 300L according to its original layout.

"Reaching ore earlier than expected is significant. It tells us the ore zone possibly extends further than our model showed or that another potential mineralised body is present," CEO Gordon Thompson says.

"We will continue the investigation and stockpiling this fringe ore while we continue towards the expected higher-grade zone. Our incline development remains on schedule, so this is a positive development.

"The bornite and chalcopyrite showing in the sidewalls, now confirmed by the assays, is exactly what we have been working towards," he adds.