Uranium from Rare Earth Deposits

(Updated February 2019)

  • A large amount of uranium is in rare earth deposits, and may be extracted as a by-product. 
  • Higher uranium prices and geopolitical developments would enhance the economic potential for recovering these.
  • Rare earths are essential for many modern technologies. Growth in electric car use will depend, in part, on the the availability of rare earths.

In addition to the 6.1 million tonnes of uranium in the world's known recoverable resources, there are substantial amounts comprising what is known as 'unconventional resources'. Such unconventional resources, from which uranium can be produced in conjunction with other metals, have accounted for over 11% of historical uranium production. Rare earth element (REE) deposits are one such unconventional resouce. REEs have unique catalytic, metallurgical, nuclear, electrical, magnetic and luminescent properties, and play a critical role in the application of many modern technologies, including magnetic resonance imaging (MRI) machines, satellites, batteries, LED screens and solar panels. China is the leading supplier of REEs, giving rise to commercial pressure for development of deposits elsewhere.

REEs are a set of 17 chemical elements in the periodic table, specifically the 15 contiguous lanthanides plus the lighter scandium and yttrium. Scandium and yttrium are considered REEs since they tend to occur in the same ore deposits as the lanthanides and exhibit similar physical and chemical properties. REEs are in fact relatively abundant in the Earth's crust, but are rarely found in concentrations that are economically exploitable. Different REEs have similar chemical compositions, meaning that they readily bond with one another, resulting in a complex extraction process. REE resources occur in four primary geological settings: carbonatites; ion-absorption clay deposits; igneous systems; and monzanite-xenotime placer deposits. REE resources are usually reported as rare earth oxides (REO).

Types of REE

Economically and geologically there is a distinction between light REEs, or cerium earths, and heavy REEs, or yttrium earths.

Light REEs

  • Scandium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium – elements 21, 57-64.
  • Primarily produced from carbonatites and placer deposits. 
  • Large orebodies known and being exploited around the world.

Heavy REEs

  • Yttrium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium – elements 39, 65-71.
  • Primarily produced from ion-absorption clays.
  • Resources of heavy REEs are typically rarer, smaller and less concentrated.
  • Most of the current supply of heavy REEs originates in the 'ion adsorption clay' ores of southern China. Some of these provide concentrates containing about 65% yttrium oxide, with the heavy lanthanides. Uranium ores from Ontario have occasionally yielded yttrium as a byproduct. Xenotime incorporates yttrium and heavy REEs.

Samarium, europium and gadolinium can fall into either category, or with terbium and dysprosium form a middle REEs category. In 2015 Greenland Minerals said that neodymium, dysprosium, terbium, europium and yttrium were critically important for clean energy uses and had high supply risk. 

Production & reserves: China's dominance

China produces about 80% of the world's REEs, mostly from Inner Mongolia. 

Source: United States Geological Survey (USGS)

Considering REEs alone, China has 45 million tonnes (37.5%) of the world’s 120 million tonnes of REO reserves, followed by Brazil with 22 million tonnes (18.3%) and Russia with 18 million tonnes (15%).

Source: USGS

All of the world's heavy REEs (such as dysprosium) come from China. Most REE is by-product from Chinese sources such as the polymetallic (iron-REE-niobium) Bayan Obo deposit in Baotou city. There are also limited surficial clay deposits in southern China, and two in Jianxi province are exploited: Longnan, with heavy REE similar to xenotime, and Xunwu, with light REE particularly lanthanum but with little cerium.

China cut back exports of all REE from the 35,000 t level in 2010, and banned exports of terbium and dysprosium. This led to recommissioning of Molycorp's Mountain Pass mine in California, and enhanced interest in bringing new orebodies into production, including Lynas' Mount Weld in Western Australia (now about 11,000 t/yr), Nolans Bore in Central Australia and Kvanefjeld in Greenland, the latter two with significant uranium content.

In April 2011 China's Ministry of Industry & Information Technology (MIIT) under the National Development & Reform Commission (NDRC) set a production quota for REO of 93,800 tonnes, up 5% on 2010, with a quota on REO smelting of 90,400 tonnes. No new mining licences were to be granted before mid-2012. MIIT said that no extra production beyond the quotas would be allowed. China’s export quotas and tariffs on REE ended in 2015, and in 2017 the production quota was set at 105,000 tonnes.

From 2011 Inner Mongolia Baotou Steel Rare-Earth (Group) acquired five rare-earth separation companies licensed by the Inner Mongolia government. It is now known as Baogang, based in Hexi Industrial Zone, Baotou, Inner Mongolia. Its main asset is the Baiyunebo mine. This was part of the national government's effort to consolidate China's REE sector, gain more influence over pricing in the global market and ensure sustainable growth in the industry.

Particular deposits and projects

Kvanefjeld, Ilimaussac complex, southern Greenland

Kvanefjeld is the main REE deposit with major potential for uranium production, with Sorensen and Zone 3 orebodies in the same Ilimaussac intrusive complex. It was investigated intensively over 1955-86, then dropped for commercial reasons. Greenland Minerals & Energy, now Greenland Minerals, acquired the project in 2007 then with a JORC-compliant resource of 43,000 tU at 0.022% U with 6.5 million tonnes of REO at 1.07% in Lujavrite. About 3.6% of REOs are terbium, dysprosium and yttrium, i.e. 'heavy'.

Resources

228,000 tU (May 2015, JORC compliant) in four deposits: Kvanefjeld, Sorensen, Zone 3 and Steenstrupfjeld. This includes 36,600 U measured resources at 0.0257 %U, 66,000 tU indicated resources at 0.0215 %U (all in the Kvanefjeld deposit), and 125,000 tU inferred resources (in the first three deposits), all with 0.015% U3O8 cut-off

11.14 million tonnes of REO including 0.40 million tonnes of heavy REO. Also 2.42 Mt zinc as sphalerite.

Relative to other world REO deposits (especially China), Kvanefjeld has a high proportion of terbium through to lutetium (elements 65-71). There is considerable further mineral potential in the immediate area – including up to 600,000 tU according to IAEA estimates.

The maiden ore reserves (JORC compliant, May 2015) are 43 Mt proven with 352 ppm U3O8 (12,834 tU) and 500 ppm heavy REO, and 64 Mt probable with 368 ppm U3O8 (19,970 tU) and 490 ppm heavy REO. These are in the upper part of the Kvanefjeld deposit. The 2018 ‘Red Book’ lists Greenland’s reasonably assured uranium resources recoverable as 66,800 tU, and in situ as 102,800 tU in the <$260/kgU category, and total identified resources as 148,200 tU recoverable and 227,700 tU in situ in the same cost category, all attributable to Kvanefjeld.

Process
The mine and concentrator with flotation circuit will produce a REE-U concentrate containing 20-25% REO plus zinc concentrate and fluorspar by-products. Then the refinery will employ atmospheric sulfuric acid leach to produce uranium oxide by-product, then stronger acid leach followed by solvent extraction recovery, and precipitation to separate REEs. Primarily it will produce a critical rare earth concentrate (Nd, Pr, Eu, Dy, Tb, Y), with lanthanum and cerium by-products. Production is envisaged as 7900 tonnes of critical mixed REO per year, 434 tU, 15,100 t lanthanum and cerium oxides, 15,000 t zinc concentrate and 16,000 t fluorspar per year.

Metallurgical flowsheets for both concentrator and refinery were developed in 2013, and have been modified since. In collaboration with Shenghe, test work over 2017-18 at China's Institute for Multipurpose Utilisation of Mineral Resources (IMUMR) at Chengdu and Baotou Meng Rong Fine Materials Co Ltd (BTMR) achieved much higher concentrate grades than in the original feasibility study. This allows consideration of selling the concentrates, rather than further processing. In January 2019 BTMR was selected to continue the development and validation of its flotation circuit.

The concentrator is planned to be at the head of Narsaq Valley adjacent to the mine, and the refinery about one kilometre down the valley. A new port will be at the bottom of the Narsaq Valley.

Start-up costs for a 3 Mt per year plant were estimated at $1.121 billion for mine, concentrator and refinery, plus $240 million for infrastructure in the May 2015 feasibility study.

Chinese partners
The company had been seeking partners for the refinery, then envisaged offshore, and in March 2014 signed an agreement with NFC, a subsidiary of China Non-Ferrous Metal Mining Group (CNMC) to provide concentrates of heavy REOs to NFC’s new 7000 tpa rare earth separation facility in China, then under construction. A further agreement with NFC was signed in April 2015. NFC's participation in the rare earth industry comes through its subsidiary Guangdong Zhujiang Rare Earths Company, which was the first group to carry out full separation of 15 rare earth elements in China, and is recognized globally as a leader in rare earth separation technology. Uranium is not included in the NFC agreement. 

In September 2016 Shenghe Resources Holding Co Ltd, a Shanghai-based rare earths company, acquired a 12.5% stake in Greenland Minerals & Energy for AUD 4.625 million. The company welcomed this as a ‘strategic investment’. It has an option to increase its share.

The company entered a non-binding agreement with Shenghe in August 2018 for the offtake of total output of rare earth elements from Kvanefjeld in either chemical or mineral concentrate. In January 2019 Shenghe formed a joint venture company – China Nuclear Hua Sheng Mining – with subsidiaries of China National Nuclear Corporation (CNNC) for the trading and processing of rare earth minerals with radionuclides. Hua Sheng provides a formal means for importing REE-U concentrates into China and will be Shenghe's designated agent for that. It will enable finalisation of a strategic development plan for the Kvanefjeld project.

Licensing
In December 2011, a year after allowing the company's feasibility studies to include uranium, the Greenland government amended the company's exploration licence to include uranium. The company could then apply for a mining licence including uranium, then with a view to first production in 2016, followed by a long mine life. In November 2012 the Greenland government voted unanimously to support the project, including uranium, and in October 2013 it repealed the long-standing policy banning uranium development. 

In 2013 the government noted that it is Denmark's responsibility to ensure that international conventions, such as non-proliferation, are respected, since Greenland remains part of the kingdom of Denmark and its defence and foreign policies are still determined by Copenhagen. The Additional Protocol to Denmark’s safeguards agreement with the IAEA, specifically for Greenland, entered into force in March 2013.

In January 2016 the governments of Denmark and Greenland reached agreements concerning the export control and security of uranium and other radioactive substances from Greenland and the definition of competencies in the raw materials sector. The Danish parliament passed legislation on safeguards and export controls in June 2016, assuming responsibility for the application of international safeguards. Corresponding legislation was passed by the Greenland parliament in May. This creates the legal framework for uranium exports from Greenland.

In 2018 the company lodged with the government updated environmental and social impact assessments (EIA, SIA) for the Kvanefjeld project, as well as the feasibility study and JORC-code compliant mineral resource estimate and ore reserve statement. The maritime safety study is pending. Following elections in April 2018 the ruling coalition reaffirmed its support for rare earth and associated uranium extraction and acknowledged that the time to move the licensing process to the next stage of public consultations is imminent. The company has applied to the government for a mining licence to proceed with the project.

R&D
The company is involved with the EU-funded EURARE programme, designed to support the development of REO deposits in Europe. The Kvanefjeld project was selected by EURARE as a major one for demonstration of REO production, and a 26-tonne ore sample (about 1.3% REO) was processed over 100 hours at the beneficiation pilot plant in Finland by simple froth flotation to yield 2 tonnes of concentrate. The next test work stage will produce 15% REO, then the pilot plant hydrometallurgy at Aachen in Germany to give a mixed carbonate of 60% REO. At Aachen a separation plant will sort the Pr+Nd from La & Ce and from other materials. The products will be evaluated.

Mt Weld, Western Australia

Lynas Corporation has the high-grade Mount Weld mine and mill in Western Australia, with its Advanced Materials Plant in Malaysia. It is the only commercial REE producer outside China. No uranium is involved.

Mountain Pass, California

The Mountain Pass deposit was discovered by a uranium prospector in 1949. It dominated worldwide REE production from the 1960s to the 1990s, and was recommissioned to again be a major producer from 2014. Molycorp Inc spent $781 million on modernising and expanding its plant, which reached 19,000 t/yr capacity in 2012 – slightly more than US demand – and 20,000 t/yr in 2014. However, by June 2015 Molycorp had accumulated debt of $1.7 billion and filed for bankruptcy. When China restricted its exports in 2010 Molycorp had a market value of $6 billion. 

Remaining resources in carbonatite are about 1.6 million tonnes REE averaging 8.24%, with 5% cut-off. It produced both heavy and light rare earth concentrates. The company made no mention of uranium as byproduct, but thorium is present in monazite.

Molycorp was restructured in 2016 as Neo Performance Materials. In 2017 the mine was sold for $20.5 million to a consortium – MP Mine Operations – backed by China’s Leshan Shenghe Rare Earth Co, with 10% equity and with JHL Capital Group holding 65%. It is operated by MP Materials and ships semi-processed output for refining in China.

Eco Ridge, Elliot Lake, Ontario

Pele Mountain Resources Inc has received mining leases for its Eco Ridge uranium and REE orebody in Canada, 11 km east of Elliot Lake. In the decade to closure of the Stanleigh mine at Elliot Lake in 1996, the area produced REE as a commercial by-product of uranium production. The Eco Ridge deposit contains a full range of REE at 0.164% grade, including 9.5% heavy REE (including scandium, europium and gadolinium in this category, 7.4% if excluding them). Uranium grade is 0.041% U with cut-off grade 0.024%. Some 65% of the heavy REE report in the uranium leach solution without any additional milling cost. The deposit includes indicated resources of 36,600 t REO and 8690 tU, plus 56,900 t REO with 14,500 tU inferred resources (NI 43-101 compliant). An underground mine is envisaged, using underground bio-leaching and surface heap leaching, the ore being moved to the surface in haul trucks. The leachate from underground and surface will be piped to the processing facility where it will be clarified and processed in a solvent extraction circuit. Solvent extraction raffinate will be recycled to the two leach operations.

A preliminary economic assessment in 2012 suggested uranium production of 10,500 tU over 11 years. However weakening REE prices coupled with the need for hardrock underground mining meant that the Eco Ridge project was deferred in favour of processing monazite at Elliott Lake, focused on neodymium and praseodymium. The monazite would come from mineral sands tailings in other countries. In March 2015 Pele announced an agreement with Sheng Kang Ning (Shanghai) Mining Investment Co. Ltd, a subsidiary of Shenghe Resources, to develop monazite processing facilities to recover REE at Elliott Lake. However, this agreement lapsed when SKN could not get permission to use its proprietary separation technology outside China. In June 2017 the company announced the sale of the Eco Ridge project for $380,000 cash.

Teasdale Lake, Elliot Lake, Ontario

Appia Energy reports 3080 tU indicated resources and 7750 tU inferred resources in connection with rare earths.

Round Top, Texas

Texas Rare Earth Resources Corp earlier signed an agreement with Areva to take up to 116 tU per year by-product uranium from its Round Top heavy rare earth project in Hudspeth County, Texas. The 2013 preliminary economic assessment includes no uranium product and only a recommendation to perform a preliminary review of uranium potential, though 37,000 tU is identified in all classes of REE resources in rhyolite (with 70% being heavy REE). A 2015 agreement establishes a joint venture with K-Technologies Inc to develop processing technology for REE.

Nolans Bore, Northern Territory, Australia

This is a deposit of light REE with 7500 tU content at 0.016% U with 1.2 Mt REO grading 2.6%, about 135 kilometres north of Alice Springs, NT. It also contains 5 Mt of 12.9% P2O5 and 0.27% thorium (Dec 2014). Perth-based Arafura Resources intends to develop it as a REE mine from 2019. The company now plans some processing about 10 km from the mine site followed by export through Darwin of an intermediate product to an offshore refinery for final processing to recover six rare earth products – lanthanum oxide, cerium oxide, NdPr oxide, SEG (Sm+Eu+Gd) oxide, HRE oxide ('heavy' rare earth oxide – Tb+Dy+Ho+Er+Tm+Yb+Lu+Y) and cerium carbonate. Phosphate and uranium may be co-products. Thorium will be separated as an iron-thorium precipitate for long-term storage at the mine site as a possible future energy source. Initial plans were to rail its concentrate at Whyalla, South Australia where it would be processed to produce 20,000 t/yr REO, 130 t/Uyr, plus phosphoric acid and gypsum co-products. The combined neodymium/praseodymium (NdPr) content of the ore means that NdPr oxide wolud generate about 80% of projected revenue, though these are both light REE. A feasibility study is proceeding and in September 2016 the project was awarded major project facilitation status by the Australian government.

Dubbo Zirconia Project, New South Wales, Australia

Alkane Resources' DZP has REE as potential by-product of zirconium production – 700,000 t zirconia as measured resources in 2011. These have 0.75% REO and 0.014% uranium – about 4200 tU, and the same in inferred resources. The 2012 reserve figures also have 0.75% REO at same tonnage but do not include uranium.

Zandkopsdrift, South Africa

Frontier Rare Earths in 2011 reported NI 43-101 resources of 950,000 t REE (56% indicated resources) at this deposit in the Northern Cape Province. The resource includes 47 ppm U, which is more likely nuisance than by-product. Frontier has signed a definitive agreement with KORES to develop the project as a partner with Frontier, initially taking 10% equity but with option to go to 50% and to take a proportional amount of production. KORES is to arrange project finance for the entire development.

Steenkampskraal, South Africa

During the 1950s and to 1963 about 50,000 tonnes of monazite concentrates were extracted which had between 3.3 and 7.6% thorium. Great Western Minerals Group through Rare Earth Extraction Co Ltd was expected to resume rare earth oxide production at its 74%-owned Steenkampskraal mine, prior to filing for bankrupcy in 2015. In 2013, NI 43-101 indicated resources including the old tailings dam totalled 32,000 t REO with 8% heavy REO, and 42,100 t REO inferred resources. The updated figures included 176,000 t monazite as indicated and 278,000 t inferred resources. Thorium was to be extracted from the mixed rare earth chloride concentrate, and stockpiled at a rate of about 360 t/yr. Steenkampskraal Thorium Ltd (STL) has the rights to this thorium and was planning to refine it, in collaboration with Thor Energy in Norway. (STL is also designing a 100 MWt high-temperature pebble bed reactor – HTMR100 – to use the thorium.)

Cummins Range, Kimberley region, Western Australia

This is a deposit of light REE with inferred resource total REO of 85,000 t at 1.74%, uranium content of 0.0145% (600 tU), and 11.2% P2O5 at 1% cut-off. Subject to proving further resources, Navigator Resources Ltd contemplated developing it as a REE mine with uranium by-product, but is now delisted. It is similar geologically to Mount Weld, but with greater uranium content. It has 127,000 t total REO inferred resources at 0.5% cut-off.

Olympic Dam, South Australia

BHP Billiton’s large Olympic Dam mining operation accesses a huge orebody, with the world’s largest resources of uranium, though this is only a by-product of copper (along with gold and silver by-products). The orebody also contains some 53 million tonnes of REO (predominantly lanthanum and cerium), though these are sub-economic and there are no plans to extract them even as by-product at present. They remain in the tailings (as at many uranium mines).

Mary Kathleen, Queensland

This was a uranium mine in a REE deposit, and from which no rare earths were recovered commercially. It operated 1958-63 and 1975-82. The uranium grade was 0.10-0.15%, the REE grade about 4-5%, and the company initially had great difficulty keeping the REE assay in product below specified levels of 0.1%. The REOs ended up in tailings, and in 2015 the Queensland government was seeking expressions of interest in recovering them.

Dalur and Khiagda, Russian Federation

The Khiagda ISL uranium mine in Siberia is planning to recover REOs as by-product.

The Dalur ISL uranium mine in Trans-Ural region is planning to recover REOs and scandium as by-product.


Notes & references

General Sources

Greenland Minerals
Pele Mountain Resources
Great Western Minerals Group
Arafura Resources Ltd 
Texas Rare Earth Resources Corp
Alkane Resources
Geoscience Australia, Australian Mineral Atlas, Rare Earths
US Geological Survey, Mineral Commodity Summaries 2018

 

 

 

 

 

 

 


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