Scandium: securing supply

Materials World magazine
,
31 Mar 2017

Scandium is an emerging mineral that could have a significant role to play in delivering the next generation of electric cars, as Benjamin Bell explains. 

Scandium, or scandium oxide (Sc2O3) as it is commonly known, is a relatively scarce, high-value mineral used to produce aluminium-scandium alloys where, importantly, the resulting alloys are suitable for the manufacture of weldable aluminium products. These characteristics overcome the limitation of more traditional alloys used in automotive manufacturing, which do not lend themselves to welding due to deformation of the aluminium panels as a result of applied heat. This characteristic has limited the use of other aluminium alloys to single piece panel components such as car bonnets and boots.

In nature, scandium can be found in its oxide form in more than 800 minerals. It exhibits some characteristics that are similar to the rare earths – with its occurrence in crustal rocks around 22ppm. The smaller size of scandium’s ion allows it to react chemically with other elements including aluminum, magnesium and zirconium. Scandium is, generally more abundant than lead, mercury and precious metals, and has roughly the same availability as cobalt.

Aluminium-scandium alloys can be welded as easily as conventional steel and exhibit superior strength characteristics, broadening their potential application to integral components such as car chassis, body panels and even aircraft fuselages, where significant weight savings can be achieved. Some favourable characteristics of scandium include increased overall strength of alloy, reduced overall weight and high levels of heat and corrosion resistance. With those characteristics in mind, the automotive manufacturing industry is logically the largest potential growth market for scandium – particularly as aluminium alloys are already widely used by leading global car manufacturers to great effect.

In addition to reducing the weight of an average family car by up to 200kg and SUVs by up to 400kg, the application of scandium alloys deliver the benefit of making the bodyshell of a car more than 50% stiffer than traditional metal alloys, improving strength and driveability. The drive in demand is not only from aluminium-scandium alloys, but the potential flow-through of its use in manufacturing could deliver in terms of overall emissions reduction. The application of aluminium-scandium alloys in major automotive componentry would enable manufacturers to build lighter vehicles using smaller engines to generate the same power-to-weight performance, in turn, resulting in reduced fuel consumption and low carbon emissions. The suitable aluminium alloy need only contain 0.2–0.4% scandium or around 1kg of scandium per vehicle. In 2015 alone, more than 68 million new cars were manufactured around the world, opening up a significant market for aluminium-scandium alloys, even if adoption was limited to just 10% of total production.

The rise of electric cars 

With the electric vehicle market set to grow exponentially over the coming decade, metals such as scandium and cobalt will occupy a critical position in car manufacturers' supply chain. The push for fuel efficiency in conventional vehicles and greater range in electric vehicles will result in a significant increase in the use of aluminum alloys by car manufacturers, particularly given that aluminum scandium alloys are around 10 times cheaper than carbon fibre. The ability to produce light but extremely strong vehicles for a relatively low cost will result in greater use of aluminum alloys across the automotive industry. 

Currently, there are only three mines producing scandium in Ukraine, China and Russia – and in each case the scandium is a by-product from the extraction of other elements. As such, volumes and product quality are both unreliable and inconsistent. While scandium mineralisation is known to exist in other areas such as Norway and North America, this is in such low concentrations that extraction of the scandium is an uneconomic proposition.  

Demand for scandium also exists across civilian and military applications, including aircraft manufacturing, solid oxide fuel cell batteries and lightweight high performance sporting equipment. Some commodity experts have predicted annual demand of scandium could increase by up to 800% over the next decade. The main constraint to its further application to date is linked to uncertainty around current supply. 

Mining scandium

Despite the uncertainty of supply, Australian exploration and mining company, Australian Mines Limited, moved into the scandium market in 2016, with two separate mining opportunities in a bid to become the world’s first major, long-term producer of scandium from primary deposits. Moving away from the more traditional exploration portfolio, previously focused on gold, copper and nickel could provide the opportunity to emerge as a global leader in the supply of scandium, with agreements in Australia signed to acquire 100% of the high grade Flemington scandium-cobalt project in New South Wales and a 75% interest in the SCONI scandium-cobalt project in Queensland. Having now commenced a definitive feasibility study (DFS) on the project, the indicative development timetable targets completion of the study by December 2018, with the construction target for mining operations during 2020.

A scoping study has also commenced on the Flemington scandium-cobalt project to explore the potential of the existing scandium mineral resource as well as the preferred mining schedule and processing options. Having already begun applying for a mining licence over this deposit, scandium production from the high-grade Flemington project is expected to begin by 2022, pending a positive outcome. The main focus will be optimising production and quality to provide certainty for future partnerships. A 10% take-up of aluminium-scandium alloy across global car production would result in a demand increase of 6,800 tonnes of scandium oxide per annum, equalling more than three times the total production from the Flemington and SCONI projects over their projected 20-year mine lives.

Mining projects

The SCONI scandium-cobalt project is located near the historic mining centre of Greenvale, 250km east of the major Queensland city and port of Townsville. The deposit has simple metallurgical characteristics and a pilot plant achieved the highest possible purity of scandium oxide at 99.99%. SCONI is a low- risk operation, with previous tests demonstrating production can achieve better than 97% recovery of scandium from ore. The final processing operation flowsheet will be designed to enable expansion at any time to allow for additional processing of SCONI’s cobalt-rich ore.

As part of the ongoing DFS, a tonne of sample ore will be taken from the SCONI deposit to generate a scandium oxide powder as well as a saleable nickel and cobalt sulphate product. This pilot processing operation will use standard mining operation equipment available at most commercial assay and metallurgical laboratories across Australia. Being able to use well-established and proven methods to produce end products from the ore minimises any technical risks associated with the scandium and cobalt projects.

SCONI has a mining lease granted over the project area, while a processing plant design has previously been identified. For a project of this nature, a reliable electricity power source will be essential, with a pre-existing 66kV power supply and a back-up diesel generator facility set to be constructed during construction. The proposed water supply is already on site and an Australian Government environmental assessment has been completed.

The Flemington scandium-cobalt project is located near the regional town of Fifield in central New South Wales, 450km west of Sydney. Hosting an existing mineral resource of 3.14 million tonnes at 434ppm scandium, (2.67 million tonnes at 435ppm in the measured resource category), the Flemington scandium-cobalt project is arguably one of the highest-grade scandium deposits in the world. Based on this identified mineral resource at Flemington, this project currently includes a total of 2,085 tonnes of Sc203, with 77% of that contained within the limonitic laterite, which appears similar in nature to Clean TeQ’s, adjoining deposit, the Syerston nickel, cobalt and scandium project in New South Wales. 

Clean TeQ’s Syerston mineralisation and Flemington share the northern continuation of the Syerston ore body – separated by a tenement boundary. Both projects offer considerable exploration upsides for additional high-grade, high-quality scandium deposits as well as complementary mineralisation including cobalt and nickel.  

Discussions are now underway with a number of potential take-off partners for the scandium oxide product as well as its cobalt and nickel sulphate, produced from the SCONI project and also the Flemington mine. This could prove a game-changing discovery for scandium with grades higher than existing sources capable of meeting market expectations for demand and price. 

Benjamin Bell is a qualified geologist and geophysicist, with experience working for listed companies, government agencies and as a respected industry consultant. He was appointed Chief Executive Officer of Australian Mines Limited in November 2011, before being appointed Managing Director in January 2012