Facts about rare earth elements:
• Rare earth elements are mined for use in such products as hybrid cars, catalytic converters, wind turbines, computers and medical applications.
• They are considered to be part of the green technology industry, helping to improve energy efficiency in magnets, batteries, glass and computers.
• There are 16 rare earth elements and two main types: light and heavy. Heavy rare earths are more scarce.
• Rare earth elements are as abundant in the Earth's crust as nickel or tin, but are not generally concentrated in commercial ore deposits.
• China is the largest producer of rare earth elements, supplying more than 90 per cent of the global market. However, China has been cutting back exports to ensure it has enough rare earths for its own use.
• Demand grew from about 85,000 tonnes, or about $500-million (U.S.) in 2003, to 124,000 tonnes or $1.25-billion in 2008.
• By 2015, demand is estimated to be 200,000 tonnes or $2.3-billion.