Highlights
- EMC has filed a provisional patent application for Direct Rubidium Extraction (DRE) at its Mt Edon Critical Mineral Project, securing intellectual property rights
- The patent is a result of research undertaken by Edith Cowan University’s, Mineral Recovery Research Centre (MRRC)
- This patent application underpins EMC’s strategy to develop Mt Edon utilising new technology that increases recoveries compared to existing processes and offers an environmentally friendly processing route through DRE
- Advanced work continues on the Engineering Scoping Study (ESS), and ongoing improvement of the purification process to enhance cost-effectiveness
- Patent application validates the extraction process and supports initiation and ongoing discussions with potential offtake partners
- Grant funding options to support the next phase of pilot plant construction to be submitted over the next quarter
Everest Metals Corporation Ltd (ASX: EMC) (“Everest”or “the Company”)is pleased to announce the successful filing of a provisional patent application with the government body, IP Australia, for its proprietary rubidium extraction process utilising ore from its Mt Edon Critical Minerals Project in WA. This step secures intellectual property rights for EMC’s rubidium recovery process method.
To ensure thorough evaluation, EMC engaged the patent attorney firm Integrated IP (“IIP”) to review the new process, including conducting a subject matter search. Following this review, IIP confirmed the lodgement of the application with IP Australia.
The new process represents a significant improvement over existing rubidium recovery methods, providing additional advantages to EMC and its Mt Edon Critical Minerals Project. Test work has demonstrated high recoveries of both rubidium and lithium. The patent application also lays the groundwork for future international filings, further bolstering EMC’s intellectual property protection.
Executive Chairman and CEO Mark Caruso commented:
“Submitting the patent for the processing flowsheet marks an important milestone for EMC and the development of the Mt Edon Critical Minerals Project. This achievement of a viable process flowsheet to extract rubidium paves the way for progressing commercial and operating engineering studies as
well as continuing discussions with potential offtake partners. The board extends its gratitude to the EMC geological team and ECU’s Mineral Research and Recovery team, for their tremendous effort in reaching this pivotal stage.”
BACKGROUND
In February 2024, Edith Cowan University (“ECU”) and Everest Metals Corporation Ltd formalised a partnership by executing a Research Agreement (“Agreement”) to advance studies on the extraction of rubidium from Mt Edon ore[1]. The research was conducted at ECU’s Mineral Recovery Research Centre (“MRRC”) over a 12-month period.
The initial phase of the collaboration involved a small-scale laboratory demonstration of the complete process for rubidium recover. The Direct Rubidium Extraction (“DRE”) test work and studies used cutting-edge methods, including ion exchange, to explore the potential to commercialising Mt Edon’s ore. The focus was on leveraging DRE technology to efficiently recover rubidium.
This partnership addresses the growing demand for sustainable and environmentally friendly extraction methods. The research aimed to develop a state-of-the-art process that maximises rubidium and lithium recovery. By optimising operating conditions and selecting appropriate cations (positively charged ions), the project was designed to achieve maximum rubidium extraction in a cost effective and environmentally friendly method.
This approach leveraged cutting-edge technologies, innovative methodologies, and industry best practices to ensure a sustainable and profitable extraction process. The process encompasses purification and refining, ultimately leading to the conversion into a final product, such as rubidium salts and metal.
Various test work was conducted by ECU’s MRRC with results demonstrating acceptable levels of both rubidium and lithium in the leach liquor. The initial results reported by Everest in July 2024 demonstrated a technically viable rubidium recovery rate of up to 85% recovery using the DRE method[2].
To extract rubidium and lithium, two process methods were used – non-destructive and destructive. Through the destructive process method, the muscovite structure was deteriorated to gain the maximum extraction of rubidium. Several tests were conducted during this stage, and the results verified to ensure the same consistent and reliable outcomes. The maximum rubidium extraction achieved in this stage demonstrated the desired repeatability within a range of 75±10%[3].
During phase 2, two critical processes were examined: refinement and conversion. The refinement
process utilised a specific chemical as an adsorbent for the DRE method, while another chemical was employed as a precipitation inducing agent.
This dual approach allowed for effective separation of rubidium from the Mt Edon Ore. The DRE process yielded Rubidium Chloride (RbCl) as the primary product, eliminating the need for additional conversion steps. Parallel investigations of acid leaching were conducted, exploring temperature influences, and the effects of different acid types and concentrations.
Throughout these experiments, samples were systematically collected for comprehensive analysis. The analytical phase employed multiple characterisation techniques to evaluate process effectiveness.
The purification phase employed two approaches: ion exchange-based extraction and precipitation-based selective precipitation. The results demonstrated exceptional efficiency with 91% overall recovery of rubidium for synthesised brine. Of note, 92 g/t lithium was produced as the by-product[4].
A comprehensive process for rubidium extraction and recovery has been developed, providing a systematic outline of each processing stage and material flow. This process showcases an advanced method for selective ion separation and recovery, integrating both primary rubidium extraction and secondary lithium recovery pathways.
Future Activities
EMC is planning the following steps to advance its work for Mt Edon:
- Engineering Scoping Study (ESS)
A high level inital techno-economic analysis initiated for destruction process, focusing on both capital expenditure (CAPEX) and operational expenditure (OPEX).
- Purification processes
Plan to transition tests from a batch mode approach to a bench scale setup. This change will assist to optimise critical process parameters. Ultimately, these optimisations will contribute to the development of a comprehensive and effective purification process for future applications.
Mt Edon Project
Mt Edon Critical Mineral Project is located 5km southwest of Paynes Find, in the Mid-West region of Western Australia, approximately 420km northeast of Perth (Figure 1).
Mt Edon has an initial Inferred Mineral Resource (MRE) of 3.6 million tonnes grading 0.22% Rb2O, and 0.07% Li2O (at 0.10% Rb2O cut-off), contains more than 7,900 tonnes of Rb2O (Table 1)[5]. The maiden Inferred MRE includes a high-grade subset of 1.3Mt at 0.33% Rb2O and 0.07% Li2O (at 0.25% Rb2O cut-off) which is nearly 56% of the total contained Rb2O tonnes.
This verifies the tier-1 scale and grade of the Mt Edon deposit. The MRE is limited to a strike length of only ~400m within a 1.2km lithium-caesium-tantalum (LCT) pegmatite corridor and a vertical depth of ~140m below surface.
Table 1: Mt Edon Maiden Mineral Resource Estimate (JORC Code 2012)
| Category | Tonnes (Mt) | Rb2O (%) | Contained Rb2O (t) | Li2O (%) | Contained Li2O (t) |
| Inferred | 3.6 | 0.22 | 7,900 | 0.07 | 2,500 |
| Total | 3.6 | 0.22 | 7,900 | 0.07 | 2,500 |
- Mineral Resources are classified and reported in accordance with JORC Code (2012).
- Mineral Resource estimated at a 0.10% Rb2O cut-off.
- Mineral Resource is contained within mining licence M59/714.
- All tabulated data have been rounded.
Multiple geological and geophysical targets exist across the project, which along with the resource modelling that underpins the MRE, form the basis for further exploration and anticipated resource growth.
Figure 1: Mt Edon mining lease location map, southwest of Paynes Find, Western Australia
Modelling has shown the mineralisation remains open along strike to the northeast and southwest, providing immediate potential to significantly increase the MRE with follow-up drilling. The Mt Edon resource has outcrop or occurs close to surface and will be amenable to opencut mining, with the information suggesting a low stripping ratio.
RUBIDIUM OVERVIEW
Applications and Importance
Rubidium (Rb) is a critical raw material for various high-tech applications, including the development of new energy conversion technologies and new communication technologies. Key applications include:
- Defence and Military: Night vision imaging, special glass, radiation detectors, photoelectric tubes, radio electronic tubes and military infrared signal lights.
- Aerospace: Ion propulsion engines and atomic clocks.
- Communications: Ion cloud communications and fibre optic communications.
- Emerging Energy Power Generation: Materials for magnetohydrodynamic power generation and thermionic power conversion.
- Medical: Sedatives, tranquilisers and medications for treating epilepsy and synthetic alkaline solvents.
- Special Glass: Enhancing glass conductivity, increasing lifespan and stability.
- Industrial Catalysts: Widely used in ammonia synthesis, sulfuric acid synthesis, hydrogenation, oxidation and polymerisation reactions.
- Electronic Devices: Important materials for photovoltaic cells, photoemission tubes, TV camera tubes and photomultiplier tubes.
Researchers have also recently proposed the use of rubidium for chemical storage within hydrogen batteries, expanding the potential market for this critical mineral[6].
Production and Market Trends
Despite the breadth of applications and demand for rubidium and caesium and their hydrides, global production of caesium and rubidium is significantly lower than that of other alkali metals, and the cost per kilogramme is substantially higher than lithium, sodium or potassium.
Due to the gradual depletion of caesium resources, but the continued demand of these industries, a replacement is required, with Rubidium being a suitable candidate. The downstream application fields of Rubidium salts are rapidly growing, enhancing the Company’s market advantage in this sector. As a result, rubidium has been listed as one of the 35 critical minerals by several countries around the globe including USA and Japan.
According to the U.S. Geological Survey (2024)[7], global rubidium resources are relatively scarce, with most resources containing limited Rubidium content. The Rubidium Industry is expected to grow from US$4.46 Billion in 2023 to US$7.2 Billion by 2032. The rubidium Market CAGR (growth rate) is expected to be around 5.48% during the forecast period (2024 – 2032)[8].
Several market factors support growth in demand for rubidium and underpin the current price of ~US$1,200/kg[9]. Among these, there is significant global demand for newer and faster electronic products due to the rapid pace of innovation, technology advancement and R&D activities in the electronics industry. This increasing demand for rubidium, coupled with the fact that Rubidium is difficult to source due to extremely limited global production, underpins the extremely high price of rubidium products.
North America holds a significant share of the rubidium market in terms of both market share and revenue. However, like most critical minerals, China maintains control of the market. Commodity analysts believe if more rubidium was produced, the market could grow rapidly and therefore its very small market size can be partially attributed to supply constraints, rather than a lack of demand.
[1] EMC ASX Announcement: EMC To Advance Mt Edon Critical Mineral Project Through Rubidium And Industrial Mica Product Development, dated 27 February 2024
[2] EMC ASX announcement; Successful Recovery of Rubidium from Mt Edon Critical Mineral Project, dated 24 July 2024
[3] EMC ASX announcement; Successful Recovery of Rubidium from Mt Edon Critical Mineral Project, dated 24 July 2024
[4] EMC ASX announcement; Everest Metals Achieves Up To 91% Rubidium Recovery from Mt Edon, dated 18 December 2024
[5] ASX: EMC announcement; EMC Delivers World-Class Rubidium Resource At Mt Edon Project, WA, dated 21 August 2024
[6] S. Matalucci, May 2024, Researchers propose use of caesium, rubidium for hydrogen batteries, pv-magazine.
[7] U.S. Geological Survey, January 2024, Mineral Commodity Summaries 2024
[8] www.marketresearchfuture.com/reports/rubidium-market-27298
