Owen Missen – 2024 – Could harnessing natural processes be a potentially viable method to extract critical elements from mine wastes?


Our planet is not a uniform mixture. Instead, chemical elements are deposited unequally. When enrichment of an element like gold or copper is significant enough, we call this an ore and may consider whether extraction of the gold or copper is economically viable. This enrichment has occurred through natural processes, and although we are not always aware of it, all chemical elements are naturally cycled through the environment. My idea is to first understand and then use natural processes that enrich certain elements to extract critical elements from mine wastes.

Critical elements (also known as critical metals or commodities) are the raw materials that society requires to continue the transition away from fossil fuels as energy sources. The term ‘critical element’ is not a scientific one. Instead, it is a geopolitical one, reflecting a range of difficulties in securing a reliable supply of a given element (such as challenges in extracting an element from low-grade ore, or supply chain and logistic issues). Critical elements are often not major commodities, meaning they are typically concentrated in mining waste materials produced by extracting other materials.

By researching the processes that drive critical element cycling in surface environments, blueprints can be developed for enrichment of critical metals in mine waste facilities. For example, if dry conditions followed by a flush of water produce a metal-enriched aqueous solution, this metal-rich solution could be collected for further processing. This ‘reverse engineering’ method thus has potential to provide a new production method for critical metals from existing mined materials, costing less energy and having less environmental impact than finding and extracting a new resource.


Dr Owen Missen is the Environmental Geology Lecturer in Earth Sciences at University of Tasmania. He researches the environmental mineralogy and geochemistry of Critical Minerals, essential components of the green energy transition. Owen completed his PhD studies at Monash University and Museums Victoria. His Doctoral thesis focused on the mineralogy and biogeochemistry of tellurium, an element best-known as trace element in gold deposits which is gaining prominence as a component in certain solar panels and electronic devices. He has also undertaken a research project on cobalt biogeochemistry in Australian semi-arid environments at Museums Victoria following the awarding of his PhD. His Masters Thesis undertaken at University of Melbourne and Museums Victoria unravelled the crystal structures of several tellurium oxysalt minerals.

Additional Information

Link to upcoming Critical and Strategic Metals Symposium

Natural cobalt–manganese oxide nanoparticles: speciation, detection and implications for cobalt cycling

Will global cobalt supply meet demand? The geological, mineral processing, production and geographic risk profile of cobalt – ScienceDirect

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