As global efforts to reduce greenhouse gas emissions intensify, demand for renewable and low emission technologies is growing rapidly.
As a result, demand for the critical minerals and rare earth minerals that are required to build those technologies is increasing too.
One such mineral is nickel: a key component of the high-performance batteries used in electric vehicles.
But the nickel of choice for battery manufacturers – which is preferred to come from high grade nickel sulfide ore – is less abundant and more challenging to find than nickel from other sources.
Australian exploration and mining companies that are able to refine their exploration techniques for nickel sulfide will be well positioned to benefit from the strong and sustained global demand for battery-quality materials
Through targeted R&D projects, Australia’s national science agency CSIRO is working with the minerals resources industry, including smaller companies who aspire to become miners, to help in their quest to find and interpret indicator mineral systems.
Indicator minerals in magmatic nickel systems
Indicators minerals are minerals that give clues about the presence or absence of a specific type of mineralisation in a particular location.
They have been used in diamond exploration for many years: when prospectors find a particular type of garnet, it is an indicator that the host rock has been subject to the pressure and temperature that’s also required for diamonds to form.
Now a similar approach is being used in magmatic nickel systems.
Magmatic nickel sulfide deposits are formed when hot, highly liquid lava flows through the earth’s crust.
When the magma is saturated in sulfur, it forms sulfide droplets; these sulfide droplets attract and concentrate the metals present within the melt.
These sulfide droplets then coalescence and accumulate within mafic and ultramafic intrusions and lava flows, and if there is a large enough accumulation of metal-enriched sulfides, this becomes a mineable deposit.
“There are two kinds of indicator minerals that we can look at,” says Dr Margaux Le Vaillant, CSIRO’s Ore Body Geoscience Group Leader.
“In situ minerals are found still within the host rock; whereas ex situ minerals used to be within the host rock but have now been weathered out of it. Within magmatic nickel systems, some of the key indicator minerals we’re looking for include olivine, pyroxenes and chromite.”
Historically, prospectors have looked only for the presence or absence of an indicator mineral to let them know whether an area is likely to contain a target.
But CSIRO’s recent research on magmatic nickel systems goes a step further.
“Presence versus absence doesn’t actually tell us very much for these systems,” says Dr Le Vaillant.
“That approach has been used with diamonds, but now with magmatic nickel systems we are actually looking at the trace element chemistry of the indicator minerals, and what information that can reveal to us about the processes that have taken place within the magmatic system.”
Working with industry for real world impact
Dr Le Vaillant is currently co-leading a team at CSIRO on a two-year project underpinned by funding from the Minerals Research Institute of Western Australia that will help identify and characterise indicator minerals for magmatic nickel systems.
Working collaboratively with industry partners, the team hope to provide new insights to guide more effective mineral exploration.
“We’ve been doing this work in the lab for several years,” says Dr Louise Schoneveld, a CSIRO Research Scientist specialising in ore deposit petrology who is co-leading the project alongside Dr Le Vaillant.
“But with this latest project, we have really scaled up. It involves us working with eight industry partners across Western Australia – they are companies of different sizes, at different stages of exploration, with different styles of deposit. Hopefully that’s going to mean we come up with useful, practical tools for exploration that can be incorporated into existing workflows.”
Initially, CSIRO researchers will focus on individual case studies with industry sponsors including BHP, Estrella Resources and Ardea Resources.
The team’s work will help address specific research questions the companies have, and these may vary considerable from company to company.
By taking a consortium approach, CSIRO is helping smaller companies minimise risks of R&D and give multiple partners the opportunity to benefit from collective research outcomes, like enhanced expertise and knowledge.
At the same time, the case studies will allow the research team to build a diverse set of samples and a comprehensive dataset that will enable them to determine the robustness and practical use of known indicators, as well as exploring new minerals and signatures that show potential for being indicators.
“One of our biggest challenges with this research is that we need a good, well defined sample set,” says Dr Schoneveld.
“We need a wide range of compositions to help us understand what’s going on with the indicator minerals and make sure our techniques are widely applicable across different sites and environments."
"For example, if you find a loose grain of a particular indicator mineral, what does that mean, and how excited should you get? This project puts us on track to answer some of those questions.”
Access for smaller companies through an innovative funding model
One of the most exciting things about the indicator minerals project is the broad range of companies that are involved: something that has been made possible through the Innovations Connections scheme.
“Very often with this kind of major research project, you’ll only see larger companies involved,” says Dr Schoneveld.
“It has been really exciting and positive to work with smaller industry partners who are so enthusiastic and keen to learn. Our goal is very much to make sure that any technology we come up with is accessible to smaller companies.”
Even though the project is still ongoing, some of those partners are already starting to see results.
“We have a strong history collaborating with the CSIRO,” says Darren Howe, Geology Superintendent with Western Australian battery mineral company Ardea Resources Limited.
“It is always a pleasure working with the team and sharing ideas and concepts to advance geological understanding.
Relating to recent work through the Innovations Connections Program - Indicator Minerals research, CSIRO have confirmed the existence of a fertile horizon for potential nickel sulphides that Ardea recently discovered on their Kalpini project.
The outcomes of this research have helped secure EIS government grant co-funding for drilling a potential nickel sulphide target.”