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Ian Lambert, Geoscience Australia (Australia)
Yanis Miezitis, Geoscience Australia (Australia)
Mackowski Steve, Arafura Resources (Australia)
Aden McKay, Geoscience Australia (Australia)
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The market for rare earth elements has experienced a dramatic growth, with total Rare Earth Oxides (REO) demand of 85,000 t in 2003 rising to 117,000 t in 2007, and consumption predicted to increase to 180,000 t - 190,000 t by 2012. This reflects increasing uses in hybrid cars (La in rechargeable batteries and Nd in high power magnets); disk drives, speakers; petroleum catalyst (La) and autocatalyst (Ce), polishing and multi-level electronic components (Ce), and high wear resistance ceramics (Y stabilised zirconia) and glass (Ce). The largest sector by value is in the production of phosphors for televisions and energy efficient lamps (Eu, Tb).
The most significant economic minerals include bastnaesite (LnCO3F), monazite ((Ln, Th)PO4), xenotime (YPO4) and loparite (Ln, Na, Ca) (Ti, Nb)O3 and rare earth deposits commonly include thorium and sometimes phosphorus. The high prices of rare earths are caused by the costly difficulty of extracting them from the ore and separating them from one another. Future growth in existing and new applications of rare earths will be governed by reduction in cost of extraction and purification.
The main consumers of rare earths are China, the US, Japan, Korea and Thailand. China reportedly consumes about 50% of its rare earth production and the Chinese government has imposed production and export restrictions adding upward pressure on prices for rare earths and contributing to incentives for development of rare earth resources outside China.
Globally, the production and resources of rare earths is dominated by China accounting for 97.8% of the production followed by India with 2.2%. In terms of Economic Demonstrated Resources (EDR), China holds 27 Mt (32.4%) REO, followed by Commonwealth of Independent States 19 Mt (22.8%) and the US with 13 Mt (15.6%).
The largest REE deposit is Bayan Obo in China, dominantly REE-iron ores mainly in bastnasite and monazite totalling at least 48 Mt REO at a grade of 6%. The only production from a carbonatite has been from the Mountain Pass deposit in California which has 1.8 Mt REO at an average grade of about 9%. Deposits associated with carbonatite laterites include Araxa Brazil (8.1 Mt REO at 1.8%) and Mt Weld, Western Australia with 1.7 Mt at 12%. Other deposit types include Nolans Bore (vein type in alkaline rocks 577,000 t REO at 3.1%), Northern, Australia; Toongi, New South Wales (alkaline trachyte); Lovozero, Russia (peralkaline syenite).
Australia's Demonstrated Resources of REO amount to about 28.2 Mt with a further 20.6 Mt Inferred Resources. About 45 Mt of this is in the Olympic Dam deposit (∼0.5% REE) and are not currently economic. Another 3.24 Mt of REO occur in the monazite component of heavy mineral sand deposits in Australia but the extraction of REEs is not viable due to the cost of disposal of radioactive mineral by-products. Overall, only 1.2 Mt of Australia's REO, is currently in EDR resource category.
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