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ASX-listed Prairie Lithium has taken delivery of North America's largest commercial direct lithium extraction (DLE) unit comprising four columns at its Prairie project, in Saskatchewan, marking another milestone as the company advances toward Phase 1 commercial lithium production.

The arrival of the DLE unit represents a derisking event and enables the next phase of equipment installation and commissioning, which remains on track for the fourth quarter of the year.

Prairie has already established substantial infrastructure on site, including production and disposal wells, electrical infrastructure and a power transformer.

The DLE unit is about four times larger than the commercial DLE system currently deployed at Standard Lithium's Arkansas project, where a single column was installed in March 2024 and is achieving industry-leading results.

"This milestone demonstrates the scale of Prairie's Phase 1 development and our ambition to become a leading commercial DLE producer in North America," says chairperson Paul Lloyd.

Lithium produced from Phase 1 operations is already secured under a binding offtake agreement with Hydro Lithium, which will purchase 100% of production.

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.

Successful removal of coarse waste is beneficial in that it reduces power requirements in the milling circuit, lowers water requirements, and increases platinum group metal (PGM) feed grades.

With preconcentration, a head grade of, for example, 2 g/t can be as much as doubled to 4 g/t, resulting in PGMs being valuably increased in the circuit.

Displayed was a PGM grade of 1.7 g/t being uplifted to 4.8 g/t through dense medium separation (DMS), at a flotation loss of around 0.4 g/t.

Mining benefits include being able to lower the cutoff grade, which increases the reserves and provides the opportunity to extend the life of the mine, Mintek physical separation head Gertrude Marape pointed out during Mintek's PGM Day covered by Mining Weekly. (Also watch attached Creamer Media video.)

Mintek flexibly provides clients with options. "Some clients already know the techniques, the technology that they want to use. Some ask us to advise, but essentially, we work with everyone," Marape stated in providing comprehensive information on the benefits of upfront waste rejection and chrome removal in PGM circuits.

Marape was one of a dozen Mintek managers, engineers and scientists who presented in the auditorium of this 92-year-old State-owned research organisation, which is situated at 200 Malibongwe Drive in Randburg.

While typical PGM reefs are Merensky, upper group two (UG2) and Platreef, Marape also paid attention to the PGMs present in chrome reefs such as lower group (LG) reef, middle group (MG) reef and, of course, UG2 reef.

Mintek has found that it is easier to introduce a preconcentration stage on a greenfield project than it is at a brownfield project. As much as some brownfield projects were metallurgically suitable, practical implementation has generally been found to be inappropriate.

Information was provided on the recovery of PGMs from the tailings of chrome-rich MG and LG reefs as well as UG2. In the work that Mintek has done, PGMs lost in the chromite concentrate ranged from 0.7 g/t to 0.8 g/t. Displayed was also significant enhancing of chrome recovery from secondary flotation.

Mintek's studies show that upfront preconcentration is viable but mineralogy dependent.

Sometimes it works, sometimes it doesn't work, but if it works, there's value in it, because then it reduces capital expenditure and operational expenditure of plants, lowers cutoff grade and also provides flexibility in the cases of PGM extraction being amenable to mechanised or conventional mining methods, Marape noted.

Moreover, Mintek's experience regarding interstage chrome removal is that it provides better yields and higher chrome recovery but that this will be accompanied by some loss of PGMs to chromite concentrate.

In addition, PGMs and chrome are recoverable from MG, LG and UG2 reefs, which uplifts revenue potential.

PGMs come mainly from the Bushveld Igneous Complex's three limbs – the western, eastern, and northern limbs.

While typical reefs are Merensky, UG2 and Platreef, there are also PGMs in chrome reefs such as LG reef and MG reef.

While LG and MG reefs are initially mined mainly for their chrome, PGMs are there for the taking in LG and MG tailings.

Displayed were infographics showing typical upfront coarse waste rejection, done after crushing and before milling.

Most of the reefs have a lot of pyroxenite gangue in them and the rejection of this coarse waste in them can be through DMS or through sorting – dry on-site processing – depending on which is more beneficial and with greater throughput also being taken into consideration.

Mintek used to provide on-site sorters but now has partnerships with various sorting companies and can link clients to these suppliers.

The purpose of coarse waste rejection is to rejec...

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.

ASX-listed Viridis Mining & Minerals has upgraded the mineral resource estimate (MRE) of its Colossus rare earths project, in Brazil, following targeted infill drilling.

The measured and indicated MRE of the project is now an industry-leading 305-million tonnes grading 2 723 parts per million (ppm) of total rare earth oxides (TREO) and 659 ppm of TREO, respectively.

Notably, the programme identified a measured mineral resource of 31-million tonnes grading 2 858 ppm TREO and 758 ppm mixed rare earth oxides (MREO), providing the company with a high-confidence resource foundation for the highest-value years of planned production supported by outstanding project economics, strong early cash flows and rapid capital payback.

Viridis reports the Colossus mineral resource totals 473-million tonnes grading 2 505 ppm TREO and 592 ppm MREO. High value magnet rare earths continue to comprise 24% of the TREO within the measured and indicated resource.

Viridis says the substantial measured mineral resource supports an anticipated conversion of the initial production schedule to proven ore reserves as part of the project's definitive feasibility study. This satisfies a key requirement for project debt financing and represents a major step towards a final investment decision on the project during the second half of the year.

"The Colossus project continues to set the global benchmark for ionic adsorption clay rare earth developments through its combination of world's highest-grade measured and indicated MREO mineral resource, industry-leading measured resource grade supporting the early years of planned production, proven reserve conversion pathway supported by exceptional geological confidence, industry-leading metallurgical recoveries using a near-neutral pH leach process and significant potential for further resource growth," explains Viridis MD Rafael Moreno.

Moreno mentions that the current MRE covers only 12% of Viridis' landholding, however, Colossus already hosts almost half a billion tonnes of mineralisation and the world's highest-grade measured and indicated MREO resource.

"This is not just a geological milestone, it is a financing milestone. Defining more than five years of measured resources for the initial mine plan satisfies a key technical requirement for project debt financing," Moreno says.

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A lower-risk secondary mining business, which focuses on extracting value from platinum group metals (PGM) surface waste that hosts chrome, is being built by the South Africa PGM Operations of Sibanye-Stillwater.

The opportunity lies in unlocking PGM and chrome value from the large, accessible upper group two (UG2) tailings resources on surface.

UG2 tailings retreatment, fine chrome recovery and processing capability are creating a new value stream.

The first part of the surface processing strategy – Phase 1 of the WLTR recovery plant upgrade project – has already arrived.

This phase, which involves treating tailings to recover chrome as well as PGMs, supports the broader South Africa PGM Operations surface retreatment strategy.

The feasibility study has been completed, board approval has been received, and construction is scheduled to begin in the second half of this year, with commissioning expected by the end of 2027, Sibanye-Stillwater executive VP processing Lucas Msimanga reported during the Capital Day covered by Mining Weekly. (Also watch attached Creamer Media video.)

The projected capital is R0.9-billion, payback is two years, Phase 1's economic life is six years, net present value is R1-billion, internal rate of return is 43%, and operating costs were described by an upbeat Msimanga as being "very competitive".

Historical UG2 tailings storage facilities (TSFs) across the Rustenburg and Marikana regions provide the material, the primary value driver is chrome coupled to meaningful PGM upside, and available PGM concentrator capacity offers the capability of recovering PGMs in an integrated and efficient manner.

With a switch to magnetic processing technologies, the surface resources also present a significant chrome recovery opportunity.

A million tons of historic UG2 tailings are there for the taking and Sibanye-Stillwater has vast processing and tailings infrastructure spread across 70 km of PGM footprint to handle current and future mining output.

The Johannesburg Stock Exchange- and New York Stock Exchange-listed mining and marketing company's vast footprint takes in Marikana as well as the Rustenburg region, and within the footprint are concentrators for primary processing of the material from the underground operations.

Capacity is adequate to process the current and future projects. Total available concentrate capacity across Sibanye-Stillwater's South Africa PGM operations is 1 605 000 t a month.

All of this is linked to long-term TSFs. The life of the Paardekraal TSF in Rustenburg extends to 2060, as does the Marikana Pits TSF and Hoedspruit in Marikana extends to 2044.

"We've got the capacity to dispose of those tailings safely, as well as in an environment-friendly manner.

"When processing, we continuously seek to improve recoveries. We're benchmarking internally as well as externally, and we want to raise recoveries as high as possible," Msimanga pointed out.

Standout 36% recovery is being achieved by the WTD5, Hoedspruit and Marikana Pits TSFs, with recoveries from the other TSFs ranging from 11% to 17%.

"Our objective is to get close as possible to the 36%, which will be done by optimisation of the TSF operations and the deployment of the right technology," said Msimanga, who drew attention to the focus of Sibanye-Stillwater's seven relatively shallow primary adjoining mining projects also being largely on UG2 reef, which, provided the company continues to invest appropriately across concentrators, supports operational reliability.

Targeted sustaining capital has maintained high equipment availability and recovery performance. This approach supports structurally lower unit costs.

The result is a flexible processing platform that supports processing requirements of curren...

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.

Hundreds of workers at BHP's Port Hedland iron-ore operations in Western Australia could walk off the job next week, in what would mark the biggest industrial action there in decades, potentially disrupting $80-million of daily revenue for BHP.

The unions have called for the action, an eight-hour work stoppage set for July 16, after six months of negotiations that have failed to reach an agreement on terms for a four-year labour deal. The action is set to run from 2 pm to 10 pm (06:00 to 14:00 GMT).

Some 160 to 200 employees of the 450 workers who cover BHP's port and maintenance operations will walk off the job, according to the Combined Ports Unions, which represents four unions active at the site.

"This is nobody's preferred way forward, but when it is our only way forward, we will take it," said Adam Woodage, the secretary of the Electrical Trade Union Western Australia.

"I hope this sharpens the minds of BHP managers - and shareholders - on the importance of negotiating for a fair, safe and productive iron ore industry."

Union officials said a meeting with BHP was slated for Tuesday that could avert the stoppage.

The action comes after workers at some of BHP's other operations in the Pilbara region where Port Hedland is located narrowly voted last week to approve a new labour agreement.

"We have delivered a new enterprise agreement at Mining Area C and South Flank that rewards 1 800 workers -- without industrial action," BHP said in a statement on Wednesday.

"Every Australian benefits from a strong iron ore sector. We are eager to keep negotiating constructively for a fair deal, while making sure we can keep operations running safely."

BHP shares fell 2.9% on the day to A$57.19 ($39.70), slightly outpacing losses among other miners and compared to a 0.5% decline for Australia's benchmark stock index.

Unions are making the biggest push in 30 years to penetrate Australia's mining heartland, emboldened by a Labor government law in 2022 giving them the power to negotiate wage deals that cover several employers, allow more scope to request flexible arrangements and industry-wide strikes.

The South Flank agreement last week included a guaranteed 16% pay hike over its four-year term, increases to site-based allowances and a new payment scheme for delayed flights.

"We think the South Flank deal is undercooked, for the work that they do away from their family and for the conditions," Steve McCartney, State secretary of the Australian Manufacturing Workers Union, told reporters. "Sixteen percent over four years is not enough."

Mining workers are among Australia's best paid. Resources workers living in the Pilbara earned A$191 000 on average in 2023/24, according to a survey by industry group the Chamber of Minerals and Energy.

Australia's median wage for registered nurses is A$85 000 to A$100 000 according to industry bodies and the median wage is A$75 000 a year, according to government figures.

Port Hedland, which is also used by miners Fortescue and Hancock Prospecting, ships around $150-million of iron-ore a day.