1. Section Name
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PICTURE THE PERIODIC TABLE AS A CITY. ber is expected to grow to 200,000 which are heavily concentrated in particular
You’ve got your flashy downtown: gold, metric tons. ore deposits, rare earths are sparse. The world’s
silver, and the like. You’ve got your China’s production of REEs has been richest veins of REEs contain only 4% to 9% of
industrial sector: iron and nickel. There growing steadily over the past decade. the elements. Most deposits have 1% or less of
are parks: carbon, oxygen, and nitrogen. But because its domestic demand for the elements—too little to make their process-
And of course the “troubled” section: the elements has been growing even ing economical, says Mark Smith, chief exec-
radionuclides. Then there are the forgot- faster, the country’s REE exports have utive officer of Molycorp Minerals in Green-
CREDITS (LEFT TO RIGHT): ISTOCK PHOTO; IZMOSTOCK/ALAMY
ten, distant exurbs: the rare earth elements dropped from 75% of the total produced wood Village, Colorado, the only remaining
(REEs), lanthanum (element 57) through to 25% (see figure, p. 1597). For a handful rare-earth mining company in the Western
lutetium (element 71) along with scandium of elements—neodymium, dysprosium, Hemisphere.
and yttrium. Sleepy no more, the exurbs have terbium, and yttrium—China is expected to In some cases, mining companies are
turned very desirable. In recent decades, REEs use all it can produce sometime between 2012 responding. For example, in the United States,
have become vital to a host of novel electron- and 2014, leaving the rest of the world out in the Molycorp plans to reopen a mine in Mountain
ics and green-energy technologies. The trouble cold (Science, 11 September 2009, p. 1336). Pass, California, expected to produce up to
is that, while researchers are steadily invent- “We are going to have to start acting 20,000 metric tons of rare earth oxides by 2012.
ing new applications for rare earths, the supply quickly, or we will be in big trouble,” says Ed In Canada, Great Western Minerals Group and
isn’t keeping up—and users of REEs are feel- Richardson, the sales and marketing manager Avalon Rare Metals hope to tap vast rare-earth
ing the pinch. for Thomas & Skinner in Indianapolis, one of deposits in Saskatchewan and the Northwest
Today, China supplies more than 97% the few makers of high-intensity magnets left Territories. However, rare-earth mining con-
of all REEs, and increasingly the products in the United States, which relies on REEs to sultant Jack Lifton notes that these compa-
from which they are made. Those products make its products. And with ever more appli- nies have not been able to secure all the funds
span a wide swath, ranging from phosphors cations on the horizon, Richardson says, “the they’ll need to start
in electronic displays, to magnets in disk problems we are seeing today are only going operations.
drives, cell phones, to get worse over time.” REEs aren’t the only
and MRI machines, concern. Supplies of other metals vital to
and motors in missile electronics and green technologies—such as
guidance systems. In indium and lithium—are also tightening
2000, about 60,000 as industrial uses for these materials
metric tons of rare skyrockets.
earth oxide ores were Rare earths are not rare. They
mined worldwide. are ubiquitous in soils around the
By 2014, that num- globe. But unlike gold and silver,
Rare talent. The unique electronic structure of rare earths makes them
vital for electronic displays, hybrid cars, and many other products.
1596 26 MARCH 2010 VOL 327 SCIENCE www.sciencemag.org
Published by AAAS

2. SPECIALSECTION
160 Prius, Toyota uses a kilogram of neodymium
Losing ground. China produces nearly all the
A Widening Gap for its electric engine and 10 kilograms of lan-
140 world’s rare earths. But as uses for the elements
Metric tons (thousands)
120 increase, China’s exports of them are declining. thanum for its nickel metal hydride battery. In
100 January, a Toyota supplier also formed a part-
80 agencies to back REE mining and stockpiles, nership with a mine in Argentina to supply lith-
60 says Gareth Hatch, director of technology at ium for batteries for its next generation of plug-
40 Dexter Magnetic Technologies in suburban in hybrid vehicles.
Production
20 Exports: oxides and compounds
Chicago and editor of the RealMetalBlog. Lifton says other Western companies and
Some manufacturing companies aren’t wait- governments need to act decisively, or they will
2002 2003 2004 2005 2006 2007 2008
ing for U.S. and Canadian mining companies to find themselves frozen out of the market. “We
New mining efforts are just the first step. take action. Toyota recently made a deal with have 3 to 5 years to get it done,” he says. “And
CREDITS (TOP TO BOTTOM): ADAPTED FROM M. SMITH, MOLYCORP MINERALS; TEODOR TODOROV AT THE IBM T. J. WATSON CENTER; IZMOSTOCK/ALAMY
Numerous rare earth oxides are invariably a rare-earth mine in Vietnam, securing sup- we haven’t even started yet.”
mixed together in ores. They must be separated plies of neodymium and lanthanum. In a single –ROBERT F. SERVICE
and purified, reduced to metallic form, and then
alloyed, cast, and shaped. All the Western busi-
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nesses that used to do these extra jobs are gone Mission: Irreplaceable?
and will need to be restarted.
Setting up this full suite can cost hundreds SCIENTISTS ARE SCRAMBLING TO DEVELOP SUBSTITUTES FOR SCARCE ELEMENTS
of millions of dollars and take up to a decade critical to industry. But the myriad uses of the elements make the effort an uphill struggle. “It’s worth-
to accomplish, Lifton says. That’s enough to while to try and find replacements,” says Peter Dent, vice president for business development at Elec-
scare away most investors, who are interested tron Energy in Landisville, Pennsylvania. “But it won’t be easy.”
in shorter term payoff. Investors also worry Dent’s company makes high-powered magnets used in electrical generators. Magnets have
about a business that can be so easily manipu- increased in strength more than 100-fold over the past century—most dramatically in the 1970s
lated by a single government, says Jeff Green, and 1980s, when researchers added samarium and neodymium to magnet alloys. The rare earths for-
president of J.A. Green and Co., a government tify the alloys against outside magnetic fields, says Bill McCallum, a materials scientist at Iowa State
relations firm in Washington, D.C., special- University and Ames Laboratory in Ames, Iowa. Such fields can easily depolarize (demagnetize) a
izing in rare earths. China seems unlikely to magnetic material such as iron, McCallum notes, because iron lacks strong “anisotropy,” or preferred
flood the market today, but it did just that in orientation of its north and south magnetic poles.
the 1980s and 1990s, driving most Western Adding neodymium, which has a strong anisotropy
producers out of business. “It creates a really thanks to its electron structure, creates a much more
unstable investment situation,” Green adds. powerful alloy. That property will be hard to replace,
Green, Lifton, and others say plenty can says Jack Lifton, a rare earths consultant in suburban
be done to get over such hurdles. Last month, Chicago, Illinois.
magnet industry leaders in the United States Nevertheless, researchers are trying. George
sent a letter to John Holdren, director of the Hadjipanayis, a physicist at the University of Del-
U.S. Office of Science and Technology Policy aware, Newark, says he and colleagues recently
in Washington, D.C., calling on the Obama received funding to develop high-strength mag-
Administration to take prompt action to restore netic materials made from neodymium, iron, and
rare-earth mining and processing in the United boron nanoparticles that they developed in 2007. New recipe. Experimental CTZS solar cells
States and other Western countries. The recom- Neodymium-iron-boron magnets are the stron- at IBM are rare-earth–free.
mendations included establishing short-term gest conventional magnetic materials; mixing the
stockpiles of rare earths critical for defense elements at the nano-scale should yield at least as much magnetization with less neodymium,
needs and having the U.S. Department of Hadjipanayis says. First, though, the team must make large three-dimensional collections of such
Energy set up a $2 billion loan-guarantee pro- nanoparticles and align their crystallographic axes—so far, a tall order.
gram to help Western mining companies build Other efforts are further along. Solar cell makers have been working for years to perfect semi-
new mining and processing facilities. Con- conductor alloys made from ultrathin films. The most successful use indium, the price of which has
gress has already drawn up a bill to push spiked to more than $1000 a kilogram in recent years. Researchers have made alternative versions
such efforts, though it has yet to be from abundant elements, such as copper, zinc, tin, and sulfur (CZTS). And last month, researchers at
introduced. IBM reported in Advanced Materials that they had increased the sunlight-to-electricity efficiency of
Such efforts could get a boost CZTS cells by 40%, to 9.6%—less efficient than indium-containing cells but close to the threshold
early next month when the Gov- of 10% considered critical for commercialization.
ernment Accountability Office Researchers around the globe have also been toiling to replace indium used in transparent con-
(GAO) is scheduled to release ductors in electronic displays. Last year, a team led by materials scientist Yang Yang of the University
an interim report on the vulner- of California, Los Angeles, reported in Nano Letters that it had developed highly conductive transpar-
ability of defense applications to ent films by layering graphene (single-atom-thick sheets of carbon) and carbon nanotubes. The films
rare-earth shortages. If GAO deter- aren’t as good as ITO yet. But an analysis last year by Nano Markets, a market research firm in Glen
mines that particular rare earths are Allen, Virginia, suggests that novel transparent conductors could soon find widespread use.
vital to national security, it “could really –R.F.S.
get the ball rolling” in prompting government
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