Until now, the global annual production of rubidium, estimated to be only a few tonnes, has likely come exclusively from China.
Among technology metals, rubidium is a niche product. Despite being twice as abundant in the Earth’s crust as copper, only a few tonnes are produced each year. This limited output is not due to scarcity, but because rubidium has so far found use only in a handful of highly specialized applications, including fiber-optic networks, night vision devices, atomic clocks, and certain epilepsy medications. Moreover, rubidium is not mined directly but is extracted as a byproduct of the mining of other metals, such as lithium and cesium.
However, demand for rubidium could rise as it finds new applications in growing sectors such as military technology and emerging fields like quantum computing. Data on the production and annual output of rubidium remains limited. Even the U.S. Geological Survey (USGS) can only speculate (PDF), naming China as the sole likely producer. Elsewhere, rubidium extraction was discontinued decades ago.
That may soon change. Australian mining company Everest Metals Corporation (EMC) has announced a breakthrough (PDF), positioning itself as an emerging producer of rubidium. A technical feasibility study released this week outlines plans for rubidium extraction at EMC’s Mt Edon project site. According to the study, a process developed in collaboration with Edith Cowan University has achieved recovery rates of up to 97% from ore samples. The process includes mining and ore processing to concentrate rubidium-bearing minerals, followed by roasting, leaching, and crystallization to produce rubidium chloride.
EMC is aiming for an annual production of up to one tonne, with the Mt Edon deposit estimated to contain approximately 7,900 tonnes of rubidium oxide. Located in Western Australia, the Mt Edon site is also considered promising for the extraction of cesium, tantalum, and lithium, the latter of which emerges as a byproduct in EMC’s processing workflow.
Next steps for the company include further testing of the technology and pursuing national and international funding. EMC aims to construct a pilot plant by 2026.
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