Cornish Lithium becomes first company to produce lithium hydroxide mined and refined in the UK

The monthly Cornish Mining Sundowner postings include news of any mining developments down here in Cornwall.  As I will be in Cape Town this month I will miss the sundowner, so I am happy to report here of the exciting new development at Cornish Lithium's Trelavour demonstration plant, near St. Austell in East Cornwall, where in a first for the UK, it has started production of refined lithium hydroxide monohydrate (LHM),  extracted from zinnwaldite, a lithium containing mica found in the decomposed granite which forms kaolin, and mined in the St. Austell region as china clay. LHM is a key raw material for advanced, high-energy lithium-ion batteries which form the foundations of nearly all modern-day electronics on which we all rely - from electric vehicles (EVs) and smartphones to energy storage and drone technology.

Cornwall is home to the largest lithium deposits in Europe and has enough lithium to power at least 50% of all EVs expected to be produced in the UK by 2030. This announcement marks a major advance in UK industrial capability that will help secure a domestic supply of a key material for UK industry. Currently over 60-70% of the world’s lithium refining takes place in China.‌‌‌​​‍‌‌‌‍‍‌‍‌‌‌‍‌​‍‌‌​​‌​‌​​‍‌‌​​‌​‌​​‍‌‌​​‍​​‍​​‍​‌‌‍​​‌‌‌‍‌‌​​​​‌‍​‌​‍‌​‍​‌‍​‍​​​‍‌‌​​‍​​‍​‍‌‌​‌‌‌​‌​​‍‍‌‌​‌‍‌‌‌‍​‌‌​​‍‌‍‌​​‌‍‌‌‌​‍‌​‌​​‌‍‌‌‌‍​‌‌​‌‍‍‌‌‌‍‌‍‌‌​‌‌​​‌‌‌‌‍​‍‌‍​‌‍‍‌‌​‌‍‍​‌‍‌‌‌‍‌​​‍​‍‌‌ 

In an end-to-end industrial process, the company is re-purposing a former china clay quarry and, using innovative low-carbon processing technology, producing refined LHM on a single brownfield industrial site at Trelavour. The custom-built facility incorporates all processing stages from crushing and grinding the rock, separation of the lithium-bearing minerals and processing of these minerals to produce a refined lithium hydroxide monohydrate.

Launched only a year ago, the plant uses patented, low-carbon processing technology developed over many years of intensive research and development. In early 2025, Cornish Lithium successfully acquired full intellectual property and associated patents from Australian company Lepidico. The Lepidico process has shown to be highly effective and has now been fully optimised by improvements made at the Demonstration Plant. Cornish Lithium plans to market the technology internationally given the success that has been achieved in recent months. The new technology, incorporated into the demonstration plant operates at atmospheric pressure and at moderate temperature, significantly reducing carbon emissions and helping to set a new sustainability standard in the sector

Following the success of the demonstration plant, Cornish Lithium plans to build a full-scale lithium processing and refining plant with an annual capacity of up to 10,000 tonnes of LHM, which is expected to commence full-scale production in 2029.

Let's not forget, however, that another company in East Cornwall, British Lithium, is also extracting lithium from the decomposed granite at a nearby china clay pit, owned by Imerys, a French multinational company, which, in 2023, acquired an 80% stake in British Lithium. The transaction brought together Imerys’ expertise in mining, R&D and process development capabilities, as well as its lithium mineral resources, with British Lithium’s bespoke technology and state-of-the-art lithium pilot plant, which last year produced battery-grade lithium carbonate.

Lithium carbonate is a major product, the foundation of the lithium industry, but for many high-end EV batteries lithium hydroxide is the preferred precursor, so refining to hydroxide gives access to these higher value battery markets. Cornish Lithium's aim of producing battery-grade lithium hydroxide signals that they are aiming at a more advanced stage of processing and potentially higher margin / higher specification product. 

By contrast, British Lithium’s achievement is important, but is at the carbonate stage. The step to hydroxide is one further stage of processing, so in principle Cornish Lithium is one further step along the chain. The fact that Cornish Lithium can produce lithium hydroxide domestically is a “first” in the UK context and by-passing a lithium carbonate stage aligns Cornwall with the trend for high-performance battery chemistries.

Weir Minerals expands its role as a total process partner in comminution and beyond

We are pleased that Weir Minerals, who sponsored Comminution '25, will be sponsoring Comminution '27 in 18 months time. The company has come a long way over the last 20 years, when it was best known for slurry-handling equipment, with hydrocyclones, pumps, and valves its core offerings.

Weir marketing their hydrocyclones at Hydrocyclones '03 in Cape Town

The company has significantly broadened into comminution equipment over the past decade and now positions itself as a "total process partner" across the entire minerals processing flowsheet, including comminution, classification, transport, and tailings management. Weir has invested heavily in, and now manufactures or supports, several categories of comminution machinery.

Weir’s Enduron® High Pressure Grinding Rolls (HPGR) line is central to its sustainability push, marketed as using up to 40% less energy than traditional grinding mills. To complement its Enduron® range of HPGRs, Weir has developed a robust range of crushers and screens under the same premium brand, now further strengthened by its in-house screening media. Weir’s large Enduron Elite double-deck banana screens have been in high demand, and will soon be produced at the company’s Alrode facility south of Johannesburg.

Large vibrating screens are vital to complement large capacity crushing plants and HPGR circuits and the Enduron Elite range is playing an important role in hard rock mining developments throughout Africa.

The latest generation of Weir’s Enduron cone crushers and jaw crushers has also just been introduced.

A key factor behind the success of Enduron HPGRs and the complementary crushers and screens in the circuit has been the rising cost of electricity, affecting not only South Africa but many other countries in Africa. Mines are adopting HPGR circuits as an energy efficient alternative to the traditional semi-autogenous grinding (SAG) mill circuits.

At Comminution '25 we were pleased to hear that the company has developed a new Process and Applications Academy, a training program designed to give graduates technical insights into processing equipment. 

The academy aims to impart essential technical knowledge to recent university graduates, ensuring they are prepared for their professional responsibilities. It is designed for graduate process engineers, mechanical engineers, metallurgists and chemical engineers. The inaugural academy also welcomed graduates in electrical and civil engineering, thereby remaining open to all graduates nominated by their respective line managers.

At the inaugural training session, the academy emphasised essential concepts, selection criteria and troubleshooting techniques, with a particular focus on comminution, slurry and dewatering pumps, wear-resistant products, valves and cyclone simulations. Additionally, the course addressed the integration of artificial intelligence into these processes, which is bringing together equipment expertise, metallurgy, and intelligent solutions to optimise entire circuits, not just machines. From real-time digital twins to predictive maintenance and mine-to-mill feedback loops, Weir's vision is helping reshape mining operations and we hope to see the company involved not only in Comminution '27 but also in MEI's inaugural conference, AI in Mineral Processing '27, which follows 2 months later in Cape Town.

#Comminution27

October summary; registration closure and a brief glimpse of dystopia

On the 13th of this month, I switched on my laptop only to discover there was no internet access. I reached for my phone to use mobile data- no signal there either.

It turned out to be a major outage affecting my broadband and mobile provider, Vodafone. Although it lasted only a few hours, it offered a brief glimpse into a dystopian scenario: a global outage triggered by a cyberattack or a huge coronal mass ejection. It was a stark reminder of just how dependent we’ve become on electronics in our daily lives.

Fortunately, the internet returned just in time for us to close registrations for Flotation '25, having reached full capacity at Cape Town’s Vineyard Hotel. This will be the largest MEI Conference in our long history, and we extend heartfelt thanks to the global community for their incredible response and continued support. If you missed out this time, stay connected with us here for updates, highlights, and news about future MEI conferences.

We are particularly excited about leaving for Cape Town in two weeks' time, as there will be a new member of the team with us, Amanda's son, Will, who will be serving his "apprenticeship" with MEI with a view to joining us in a few years time. So look out for Will if you are at the conference- you may recognise him as he was also at Flotation '07 eighteen years ago.

As soon as the dust settles on Flotation '25 we will be working on our next two conferences at the Vineyard, April's Physical Separation '26 and Mineral Processing Circuits '26. If you would like to submit abstracts to these conferences, the official deadline is tomorrow, but there is some latitude as we will not be drafting the programmes until later next month.

Gravity Mining to showcase advanced fine gravity separation technology at Physical Separation '26

We were delighted to welcome Gravity Mining Ltd as a first-time sponsor of an MEI event for the online conference Physical Separation '22, held at the height of the Covid pandemic. Now, we are pleased to announce that the company will join us again, this time in person, as a sponsor of Physical Separation '26, taking place next April in Cape Town.

Gravity Mining is the home of the original Mozley Multi Gravity Separator (MGS), a technology that has undergone significant refinement in recent years with a focus on reliability and user-friendliness. Technical Director Treve Mildren, who worked closely with MGS inventor Richard Mozley as a Design Engineer, founded Gravity Mining to build on Mozley’s legacy. The company has since continued to innovate in fine and ultra-fine mineral recovery.

Earlier this year, I had the opportunity to view the latest evolution of this technology, the massive C910 Multi Gravity Separator, at Gravity Mining’s new facility in Blackwater, near Redruth, Cornwall. Specifically designed for bulk commodities such as iron ore and chromite, the C910 enables the recovery of ultrafine minerals typically lost to tailings. Impressively, 70% of its components are sourced locally in Cornwall.

At the launch of the C910 MGS with Gravity Mining Directors
Colin Colino, and Treve and David Mildren

Headquartered in the historic hard rock mining region of Cornwall, in the far southwest of England, Gravity Mining maintains a strong export focus, with established dealers across key mining hubs worldwide. While the MGS has traditionally excelled in tin, tungsten, and tantalum applications, its use is expanding into areas such as chromite, barytes, waste recycling, and other sectors where fine gravity separation is essential. One particularly promising area for future growth is the recovery of fine free gold, a currently underdeveloped application for the MGS.

In addition to its flagship gravity separators, Gravity Mining also manufactures and supplies a broad range of supporting products, including Mozley Tables (Superpanners), Stirred Mills, Bottle Rollers and Peristaltic Pumps. The company collaborates closely with other original equipment manufacturers, producing High-Speed Centrifugal Concentrators, Spirals, and Shaking Tables to help optimise customer processes.

Gravity Mining is set to have a strong presence at Physical Separation '26, both as an exhibitor and through technical presentations on their latest developments.

A reminder to all prospective contributors: the abstract submission deadline for Physical Separation '26, as well as for Mineral Processing Circuits '26 (which follows immediately after), is the end of this week.

#PhysicalSeparation26

Memories of Nickel Processing '05, Cape Town

A week after Process Systems '05 (posting of 9th October) MEI ran another conference for the first time, Processing of Nickel Ores and Concentrates '05, the first of eventually four in the series. The event was held at Cape Town's Mount Nelson Hotel and was sponsored by Eurus Mineral Consultants.

The conference was attended by 35 delegates, and a short report was provided by Dr. Norman Lotter, of Falconbridge, Canada. Selected papers were published in Volume 19 Issue 12 of Minerals Engineering. 

A few photos from the event are shown below.

Prof. John A. Herbst: 1942-2025

There was sad news from USA this weekend of the death, on Friday, of Prof. John Herbst, at the age of 83. Prof. Herbst was an Adjunct Professor of Metallurgical Engineering in the Department of Metallurgical Engineering at the University of Utah. 

He gained his PhD from the University of California, Berkeley, under the supervision of Prof. Douglas Fuerstenau and as a graduate student at the University became one of the pioneers in applying population balance models to ball mill comminution.

His main focus was on modelling, simulation, optimisation and control of grinding (comminution) and flotation circuits. He provided a bridge between industry and academia and his focus on process modelling (especially in comminution and flotation) set him apart.

He served as Chair of the Department of Metallurgy and Metallurgical Engineering at the University of Utah from 1977 to 1986 and he founded the USBM Generic Mineral Technology Center for Comminution at Utah in 1982 and served as its director until 1988. 

One of his well-known students, Dr. Osvaldo Bascur, said of his supervisor "John was an outstanding Professor.  His scientific approach to mineral processing using particulate systems was very defined. His class notes were very well organised and his examples very well chosen.  He provided outstanding coaching, mentoring and support for his students at the University of Utah".

Osvaldo Bascur (right) with John Herbst and Prof. & Mrs. Kal Sastry in Cape Town, 2003

John co-founded the company Control International Inc. in 1986 (a joint venture with ARMCO) to apply modelling and control in mineral processing plants. He sold his part of the business in 1996 and formed J.A. Herbst & Associates in Salt Lake City. The overall purpose was to support companies using advanced technology in their processing operations. They developed a dynamic flowsheet simulator, a soft- sensor line for comminution, and an image analysis system for coarse size particles in grinding systems.

From 2000-2016 John was with Metso Minerals, becoming Chief Scientist and Manager of Technology Development before becoming the Robert E. Murray Chair and Professor of Mining Engineering at West Virginia University, and then Adjunct Professor at the University of Utah.

Prof. Herbst received multiple awards from professional societies and he was inducted into the U.S. National Academy of Engineering in 1992 in recognition of his contributions.

In 1995 he was the principal organiser and President of the XIXth IMPC/SME Conference and Exhibition held in San Francisco, at which his former supervisor, Prof. Douglas Fuerstenau became the first person to be awarded the IMPC Lifetime Achievement Award. John was too ill to attend the IMPC in Washington last year, where he was also awarded the Lifetime Achievement Award.

San Francisco 1995 with Doug Fuerstenau and Eric Forssberg

I first met John and his wife Cindy at the IMPC in Sydney in 1993 and in 1998 John and Cindy played very active parts in MEI's Minerals Engineering '98 in Edinburgh.

With John and Cindy and Gordon Agar in Sydney, 1993

John and Cindy with Peter Radziszewski and Barbara Wills, Edinburgh 1998

John and Cindy with conference delegates at the Glenturret whisky distillery, 1998

Since then we caught up at IMPCs in Cape Town and Quebec.

With Doug Fuerstenau and Peter King, Cape Town 2003

Cindy and John with Amanda Wills, Romke Kuyvenhoven and Osvaldo Bascur, Quebec 2016

Prof. John Herbst was a giant in the mineral processing community. He will be sorely missed by his friends around the world and we extend our condolences to his wife Cindy and all his family.