Rare Earths

Content maintained by Yanis Miezitis and Dean Hoatson

• Rare Earths
• Resources
• Production
• World Ranking
• Industry Developments

The rare earth elements (REEs) are a group of 17 metals which make up the lanthanide series of elements: lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), in addition to scandium (Sc) and yttrium (Y), which show similar physical and chemical properties to the lanthanides. The REEs have unique catalytic, metallurgical, nuclear, electrical, magnetic and luminescent properties. Their strategic importance is indicated by their use in a number of emerging and diverse technologies that are becoming increasingly more significant. Applications range from routine (e.g., lighter flints, glass polishing mediums, car alternators), to high-technology (lasers, magnets, batteries, fibre-optic telecommunication cables), to those that have futuristic purposes (high-temperature super-conductivity, safe storage and transport of hydrogen for a post-hydrocarbon economy, environmental global warming and energy efficiency issues). Over the past two decades, the global demand for REEs has increased significantly in line with their dramatic expansion into high-technological, environmental, and economic environments (Hoatson et al 2011¹).

During the past couple of years scandium bearing lateritic nickel-cobalt (Ni-Co) deposits have attracted increasing attention in response to anticipated rise in demand for scandium. Zirconia stabilised with scandium rather than yttrium as an electrolyte for Solid Oxide Fuel Cells (SOFCs) reduces the operating temperature of the fuel cell significantly, thereby providing a much longer life. SOFCs are expected to play a major role in the developing battery powered transportation industry as well as in stationary applications, such as in household electricity generation or as a substitute for coal fired power plants².

The group of REEs is variously, and inconsistently, reported by companies as light REEs consisting of lanthanum, cerium, praseodymium, neodymium and, sometimes, scandium. Heavy REEs may start with samarium, followed by europium through to lutetium. However, the heavy REEs are sometime subdivided further into middle REEs comprising samarium, europium, gadolinium, terbium and dysprosium with the remainder of the group, holmium to lutetium, referred to as the heavy REEs. Because of inconsistent reporting, the component elements of light, medium and heavy REEs are best noted in each case. The resources of REEs are usually reported as rare earth oxides (REO). Kingsnorth³ grouped lanthanum to neodymium as light REEs or Ceric, samarium to gadolinium as medium REEs and terbium to lutetium plus yttrium as heavy REEs or Yttric.

Table 1 - Distribution of types of rare earth elements in selected deposits (Arafura Resources Ltd)

The rare earths are a relatively abundant group of elements which range in crustal abundance from cerium, which is the 25th most abundant element at 60 parts per million (ppm), to lutetium, the 61st most abundant at 0.5ppm.

Table 2 - Applications for rare earth elements in the emerging technology areas

Geoscience Australia's latest estimate of Australia's rare earths reported as rare earth oxides (REO) amounted to 1.83 million tonnes (Mt) of Economic Demonstrated Resources (EDR), 0.35Mt Paramarginal and 34.48Mt in the Submarginal Resource categories.

• About 18% of Australia's EDR comprise Reserves as defined under the Joint Ore Reserve Committee (JORC) Code.
• About 82% comprises published JORC Code compliant Measured and Indicated Resources in operating mines, deposits being developed for mining and in deposits which have published scoping/feasibility studies with positive results.

There is a further 24.19Mt REO in the Inferred Resources category. About 53Mt REO (predominantly lanthanum and cerium) of the Submarginal and Inferred Resources are in the Olympic Dam iron oxide-copper-gold deposit in South Australia (SA). The REO at Olympic Dam are not recovered in current mining operations and are in the tailings storage facility at the mine site. About 5910 tonnes of mostly in the subeconomic and inferred categories were reported in 2010. In addition, about 56 140 tonnes of Paramarginal and Inferred Resources were reported as REEs.

Significant resources of rare earths are contained in the monazite component of heavy mineral sand deposits, which are mined for their ilmenite, rutile, leucoxene and zircon content. Monazite is a rare earth thorium phosphate mineral found within heavy mineral sand deposits in Australia. Using available information, Geoscience Australia estimates Australia's monazite resources to be in the order of 6.1Mt. Assuming the REO content of monazite to be about 60%, the heavy mineral deposits could hold a resource of around 3.67Mt contained REO. Currently, extraction of rare earths from monazite is not viable because of the cost involved in the disposal of thorium (Th) and uranium (U) present in the monazite.

Table 3 - Distribution of types of rare earth elements in monazite from different parts of the world (modified after Mukherjee 2007⁴).

Historically, Australia has exported large quantities of monazite from heavy mineral sands mined in Western Australia (WA), New South Wales (NSW) and Queensland (Qld), for the extraction of both rare earths and thorium. Between 1952 and 1995, Australia exported 265 kilotonne (kt) of monazite with a real export value (2008 dollars) of $284 million (Australian Bureau of Statistics 2009)⁵.

Small-scale production of rare earths has taken place in Australia but records on these activities are incomplete. The following information on historical attempts to establish a rare earth production industry in Australia is drawn from Cooper 1990⁶. In the 1950s, Zircon Rutile Ltd at Byron Bay, NSW, processed a small quantity of monazite to produce cerium oxide for use in glass polishing. In 1969, Rare Earth Corporation of Australia Ltd, operating at Port Pirie SA, began producing cerium, lanthanum, yttrium and thorium compounds from locally produced monazite. However, the plant ceased operations in mid 1972 because of a lack of working capital and difficulty breaking into world markets for processed rare earths.

In January 1987, it was announced that the French chemical company Rhone-Poulenc proposed to build a two-stage monazite processing plant at Pinjarra in WA to produce rare earths from monazite, but the project was suspended. Deckhand Pty Ltd, a wholly owned subsidiary of Currumbin Minerals, was blocked in 1988 on environmental grounds from establishing a rare earths processing plant at Lismore, NSW. SX Holdings Ltd of SA was planning to establish a plant at Port Pirie to process monazite with a 2000 tonnes per annum (tpa) cracking and separation plant but the project did not proceed.

Barrie (1965)⁷ reported that a pegmatite deposit six kilometres (km) east of the Cooglegong crossing, WA was worked in 1913 and 1930 and yielded about 2 tonnes of gadolinite (yttrium iron beryllium silicate (Ce,La,Nd,Y)₂FeBe₂Si₂O₁₀). An analysis of Cooglegong gadolinite yielded 45.78% of yttrium trioxide (Y₂O₃) and 4.81% of other REO. It should be noted that gadolinite does not contain more than trace amounts of gadolinium.

In 2007, mining operations commenced at the Mount Weld deposit in WA and around 98 000 cubic metres of ore has been stockpiled pending the completion of a concentration plant at the mine site. There has been no recorded production of REO in Australia during the period 2007 to 2009.

Globally, the production and resources of rare earths are dominated by China, which accounts for about 94% of production and is expected to fall to 70% by 2015 (Roskill, 2011⁸) followed by India with about 2%. These figures are only approximate because the production for the Commonwealth of Independent States, which is made up of former members of the Soviet Union, is not available.

The main consumers of rare earths are China, the USA, Japan, Korea and Thailand with China reportedly accounting for about 70% of the world's consumption in 2011 (Roskill op. cit.).

According to Roskill (op. cit.), all the growth in demand between 2005 and 2010 came from China (11% a year) while growth in the rest of the world fell by almost 4% a year, largely as a consequence of the global economic downturn in 2009 and tightening of the Chinese export quota in 2010, which restricted availability. In the years to 2015, the main demand driver will be the use of rare earths in neodymium-iron-boron (NdFeB) magnets. Demand for these magnets is forecast to grow at 11-13% per year as potential markets expand to include applications in permanent magnet motors for electric vehicles and wind turbines. Magnets could account for almost one third of demand by 2015. Strong growth in demand is forecast also for rare earths in nickel-metal hydride (NiMH) batteries, phosphors, optical glass and ceramics.

The Chinese Government has imposed production and export restrictions, adding upward pressure on prices for rare earths and contributing to incentives for the development of rare earth resources outside China. Lynas Corporation Ltd reported in its June 2010 quarterly report that export restrictions by the Chinese Ministry of Commerce resulted in a 40% decrease in available export quota rare earths in 2010 compared with 2009. This decrease coincided with the launch of a nationwide crackdown on illegal mining of rare earths in China. Lynas also reported in May 2011⁹, that demand for rare earths of 127 000 tonnes in 2010 is set to increase to about 177 200 tonnes in 2014.

China holds 55Mt (48.3%) of the world's economic reserves for REO, followed by the Commonwealth of Independent States with 19Mt (16.7%) REO and the USA with 13Mt (11.4%). Australia's EDR accounts for 1.61% of world's economic reserves with 1.83Mt REO.

The main types of REE deposits worldwide include the Bayan Obo deposit in China, which is predominantly REE-iron ores with bastnasite and monazite as the main REEs bearing minerals. The only production of REOs from a carbonatite has been the Mountain Pass deposit in California, which has total resources of 1.8Mt REO at an average grade of about 9% REO. Deposits associated with carbonatite laterites include Araxa in Brazil with 8.1Mt REO at 1.8% and Mount Weld in WA with 1.42Mt REO at 8.1%. Other deposit categories with significant REO resources include a vein type at Nolans Bore in the Northern Territory (NT) and an alkaline trachyte deposit at Toongi in NSW, along with a peralkaline syenite deposit at Lovozero in Russia.

Lynas Corporation Ltd: The Mount Weld deposit in WA is within the lateritic profile over an alkaline carbonatite complex. In September 2010, Lynas announced new resource figures for the Central Lanthanide deposit of Measured, Indicated and Inferred Resources of 9.88Mt with total lanthanide oxides (TLnO) at 10.6% and 990ppm Y₂O₃ (heavy REO) and the newly named Duncan heavy REO deposit with Measured, Indicated and Inferred resources totalling 7.62Mt at 4.5% TLnO and 2570ppm Y₂O₃ . In another part of the carbonatite complex, the Crown Polymetallic deposit, there are Indicated (1.5Mt) and Inferred (36.2Mt) Resources totalling 37.7Mt, which include total lanthanides at 1.16% and 0.09% Y₂O₃. The company completed the first stage of mining activities in 2008 and commenced construction of a concentration plant at Mount Weld and an advanced materials plant in Malaysia.

The concentration plant was commissioned in May 2011 and by the end of October, Lynas Corporation reported that the plant achieved a concentrate grade of 36.8% REO and a recovery of 64%. In Malaysia, construction of the company's advanced materials plant was 78% complete at the end of September 2011 and its September 2011 quarterly reported that the first feed to kiln was expected to occur in the first quarter of 2012. Subject to receipt of a pre-operational licence, the company anticipates the plant will reach commercial scale supply during the first half of 2012.

Arafura Resources Ltd: Nolans Bore rare earth-phosphate-uranium-thorium deposit is located 135km northwest of Alice Springs in the NT. It has Measured, Indicated and Inferred Resources totalling 30.3Mt to a depth of 130 metres which grades at 2.8% REO, 12.9% P₂O₅, 0.44  pounds per tonne U₃O₈, and 0.27% Th. According to Arafura, the distribution of the light REEs currently being considered for extraction, (La, Ce, Pr, and Nd) amount to 95% whereas the heavy REEs (Sm, Eu, Gd, Tb, Dy) amount to 4.23%. Arafura reported¹⁰ that it is planning to release a revised resource statement by the end of 2011. The company is planning to process the rare earth-phosphate-uranium-thorium ore concentrate from the Nolans Bore deposit at Whyalla in SA. Environmental studies are being conducted at Nolans Bore and at the proposed rare earths processing plant at Whyalla. Arafura have engaged AMEC Minproc to carry out preliminary engineering studies for the Whyalla processing plant. A sulphation plant and REO separation plant are being constructed at the Australian Nuclear Science and Technology Organisation (ANSTO) for demonstration trials to produce customer scale samples.

A prefeasibility study of the project was completed by Bateman, Sinclair Knight Mertz (SKM) and GHD Australia in October 2007 and a bankable feasibility study is planned for completion in 2012.

Alkane Resources Ltd: The company's Dubbo Zirconia Project located 30km south of Dubbo in NSW has a reported 35.7Mt of Measured Resource and 37.5Mt of Inferred Resources grading 1.96% ZrO₂, 0.04% HfO₂, 0.46% Nb₂O₅, 0.03% Ta₂O₅, 0.14% Y₂O₃, 0.745% total REO, 0.014% U₃O₈, and 0.0478% Th. On 16 November 2011, Alkane Resources announced a Proved and Probable Reserve for the deposit of 35.93Mt grading 1.93% ZrO₂, 0.04% HfO₂, 0.46% Nb₂O₅, 0.03% Ta₂O₅, 0.14% Y₂O₃, and 0.74% total REO. On 19 September 2011, the company released results of a definitive feasibility study which indicated a nett present value for the project of $181 million at a processing rate of 400 kilotonnes per annum (ktpa) and $1.207 billion at a processing rate of 1000ktpa.

The Australian Nuclear and Science and Technology Organisation (ANSTO) has been operating a demonstration pilot plant (DPP) for Alkane Resources at laboratory facilities of ANSTO Minerals at Lucas Heights south of Sydney NSW since May 2008 and to date has recovered substantial quantities of zirconium products and niobium concentrate. The DPP has continued to operate for short periods to trial engineering and processing innovations, and has demonstrated recovery of an yttrium-rich heavy rare earth concentrate and a light rare earth concentrate.

Navigator Resources Ltd: The company's Cummins Range carbonatite deposit occurs in the southeast part of the Kimberley region in WA. In September 2009, it reported Inferred Resources of 4.17Mt at 1.72% total REO, 11.0% P₂O₅, 187ppm U₃O₈ and 41ppm Th at a cut-off grade of 1% total REO. The total REO was subdivided into 95.6% light REO (La, Ce, Pr, Nd), 4.1% middle REO (Sm, Eu, Gd, Tb, Dy) and 0.3% heavy REO (Ho, Er, Tm, Yb, Lu). A mineralogical investigation of the Cummins Range deposit by the CSIRO Minerals Down Under Flagship was completed during the March 2010 quarter with the principal rare earth bearing minerals being primary apatite and monazite and only subordinate amounts of secondary rare earth bearing minerals are present. A rotary drilling program commenced on the deposit in September 2011.

Capital Mining Limited: The peralkaline granitic intrusions of the Narraburra Complex 177km northwest of Canberra contain anomalous amounts of zirconium, REO and low concentrations of Th (73.2Mt at 1250 grams per tonne (g/t) ZrO₂, 146g/t Y₂O₃, 327g/t REO, 45g/t HfO₂, 126g/t NbO₂, 54g/t Ga₂O₃, 118g/t Li₂O and 61g/t ThO₂, Capital Mining Limited¹¹). In the March 2010 quarterly report Capital Mining Limited reported that it was conducting metallurgical test to recover hafnium (Hf), Th, tantalum (Ta), Nb, Nd and Ce.

Hastings Rare Metals Limited: Historic exploration records reported that the Yangibana ferrocarbonatite-magnetite-rare earth-bearing dykes (ironstones) form part of the Gifford Creek Complex in WA. The dykes occur as lenses and pods and are typically the last stage of carbonatite fractionation and are enriched in REE fluorite and uranium-thorium mineralisation. The Yangibana prospect has a recorded historic resource of 3.5Mt at 1.7% REO. The rare earths are in coarse grained monazite containing up to 20% Nd₂O₅ and 1600ppm Eu₂O₃.

Marathon Resources Limited: In August 2005, the company reported that an Inferred Resource of 51 800 tonnes lanthanum- cerium is associated with the uranium deposit at Mount Gee, about 520km north northeast of Adelaide in SA.

BHP Billiton Limited: About 53Mt of the Submarginal and Inferred Resources are in the Olympic Dam iron oxide-copper-gold deposit in SA (predominantly 0.2% La and 0.3% Ce) and are not currently economic.

The historic uranium mine of Mary Kathleen in northwest Queensland is essentially a uranium-rare earths skarn deposit which has a remnant resource in tailings of about 5.5Mt at 6.4% REO +Y. Commonly occurring REE minerals in the original deposit were stillwellite and allanite while other REE-bearing minerals included apatite, titanite and garnet.

Metallica Minerals Limited: During 2010, Metallica Minerals Limited announced scandium resources within its Kokomo and Lucknow lateritic nickle-cobolt (Ni-Co) deposits in Queensland. The Kokomo deposit is 50km north northeast of Greenvale and the Lucknow deposit is 2km south of Greenvale which is about 190km west-north-west of Townsville. On 19 January 2011¹², the company reported Indicated and Inferred Resources for the Lucknow deposit totalling 6.24Mt grading at 169g/t Sc, 0.2% Ni and 0.04% Co delineated at a cut-off-grade of 70g/t Sc. The company's Measured, Indicated and Inferred Resource for the Kokomo deposit total 9Mt grading 109g/t Sc, 0.24% Ni and 0.03% Co associated with a lateritic Ni-Co deposit of 16.3Mt at 0.67% Ni, 0.12% Co and 36g/t Sc. The total Sc resource for the two deposits amounts to 15.1Mt at 133g/t Sc, 0.22% Ni, 0.04% Co. The contained scandium metal in the two deposits amounts to approximately 2000 tonnes Sc¹³.

The Lucknow deposit includes a high grade zone at a cut-off-grade of 120g/t Sc, the Red Fort, measuring 4.12Mt of Indicated and Inferred Resources at 206g/t Sc, 0.21% Ni and 0.05% Co.

Metallica Minerals Limited also announced in September 2011 that it had entered a 12-15 month period of detailed feasibility and environmental studies for its nickle-cobolt and nickle-cobalt-scandium.

Jervois Mining Ltd: In June 2005 the company reported that its Nyngan lateritic nickel-cobalt-scandium-platinum deposit in NSW had a resource of 16Mt at 0.87% Ni and 0.06% Co. A scandium-rich portion of this deposit was updated in June 2009 as Measured Resources of 2.718Mt at 274ppm Sc and Indicated Resources of 9.294Mt at 258ppm Sc. Jervois formed a joint venture agreement with EMC Metals Corporation of Canada which is conducting a three phased test-work to study the recovery of scandium from lateritic ores at Nyngan.

Krucible Metals Ltd: For its Korella phosphate-yttrium deposit south of Mount Isa in northwest Queensland, the company has published Inferred phosphate and REE resources of 13.72Mt at 0.70k/t Y₂O₃ and Nd and, although dysprosium are reported to be present, the resources have not been estimated (Krucible Metals Ltd, 2011¹⁴). The Korella deposit also has an Inferred Resource of 8.3Mt at 27.36% P₂O₅ at a cut-off grade of 20% P₂O₅ (Krucible Metals Ltd, 2010). The anomalous zone of yttrium enrichment at Korella appears to remain open towards the Duchess deposit to the north. There is little published data in regard to REE resources in phosphorite in Australia. Total phosphate resources in the Georgina Basin are considered to be of the order of 4 billion tonnes (Lottermoser, 1991¹⁵), but total rare earth elements contained in the phosphorites are generally much less than 1000ppm.

1. Hoatson, D.M., Jaireth, S. and Miezitis, Y., 2011. The major rare earth-element deposits of Australia: geological setting, exploration, and resources. Geoscience Australia, 204 pp.
2. EMC Metals Corporation of Canada in a press release on 8 February 2010 on the Toronto Stock Exchange.
3. Kingsnorth, K., 2010. The challenges of meeting 'Energy' rare earths demand. IEA Standing Committee on Long-Term Co-operation Paris, 17th May 2010.
4. Mukherjee, T.K., 2007. Thorium resources in India, its mining, separation and chemical processing. IAEA Technical meeting on Thorium based fuels and fuel cycle options for pressurized heavy water cooled reactors, light water reactors and high temperature gas-cooled reactors. 22 to 25 October, 2007. Istanbul, Turkey.
5. ABS, 2009. International trade, Cat. No.5465.0, Canberra.
6. Cooper W., 1990. Queensland mineral commodity report. Queensland Government Mining Journal, September 1990. Department of Resource Industries, 383-389.
7. Barrie, J., 1965. Rare Earths, In: McLeod, I.R. (editor), Australian Mineral Industry: The Mineral Deposits. Bureau of Mineral Resources, Australia, Bulletin 72, 515–521.
8. http://www.roskill.com/reports/minor-and-light-metals/rare earths (accessed November 2011).
9. Lynas Corporation Limited, 2011. Investor presentation May 2011. 38 pp.
10. Arafura Resources Ltd, 2011. Quarterly activities report and appendix 5B for the period ending 30 September 2011.
11. Capital Mining Limited, 2011. ASX announcement, 9 November 2011.
12. Metallica Minerals Limited, 2011. Major resource upgrade as Queensland tri-metal project celebrates milestone. ASX Release, 19 January 2011.
13. Metallica Minerals Limited, 2011. Quarterly report to 30 Sept 2011.
14. Krucible Metals Ltd, 2011. ASX announcement, 10th October 2011. Inferred Resource update for Korella yttrium deposit. Announcement to the Australian Securities Exchange, 13 pp.
15. Lottermoser, B.G., 1991. Rare earth element resources and exploration in Australia. The Australasian Institute of Mining and Metallurgy, Proceedings 296, Number 2, November 1991, 49–56.