Rare earths is the layman's term for what chemists know as the lanthanides, a group of 15 elements with atomic numbers 57 through 71 that form the top line of the bottom block of the periodic table. (Scandium, atomic number 21, and yttrium, atomic number 39, are also usually categorized as rare earths.) The minerals have unique luminescent, catalytic, and magnetic properties that make them indispensable to the 21st-century economy. They are used in most per sonal electronics, as well as in the hardware of modern warfare, including sonar systems, cruise missiles, and unmanned aerial vehicles. They are critical ingredients in the super-strong magnets found in wind turbines and hybrid?electric vehicles. Solar panels, compact fluorescent lighting, and fiberoptic cable all depend on the metals. In short, they are essential to national prosperity and national security. Which is why it's alarming that for most of the past decade China has controlled 97 percent of the world's supply?and has used its near monopoly as a strategic weapon.
In 2010 a Chinese fishing trawler skirmished with two Japanese Coast Guard vessels near the Senkaku Islands, an uninhabited archipelago claimed by both countries and known in China as the Diaoyus. Japanese authorities detained the trawler's captain and 14-man crew. A week later, Japan released the crew but held on to the captain. China raised the stakes by cutting off Japan's supply of rare earths, materials essential to the country's auto and electronics industries. The day after the media reported China's action, Japan released the captain.The incident was a blunt reminder to the world's industrialized nations of their vulnerability to Chinese economic blackmail. "These are critical resources and arguably are going to be even more important in the years ahead," says Peter W. Singer, a senior fellow in foreign policy at the Brookings Institution. "Whether it's flat screens for your jet fighter or flat screens for your den, we're already seeing [trade disputes], and I think it's going to continue."
In 2005 China exported 65,600 metric tons of rare earths, about half of what the country produced. By 2010 exports had been slashed to 30,300 metric tons, and China announced that it would reserve more material for domestic uses and begin stockpiling. Last spring, the World Trade Organization initiated an investigation into China's export practices. "Their domestic price is lower than their export price, which may not be legal," says Peter Kelemen, a Columbia University geochemist who has worked as a mineral- prospecting consultant. "And these de facto embargoes all serve to signal to people who make magnets, for example, that it might be better to manufacture magnets in China and export them than buy exported rare earths and make magnets elsewhere."
Fortunately, most rare earths are, in fact, not all that rare. They're also not all in China, which has 36 percent of the world's reserves; the United States has 13 percent. The majority of the elements are found in quantities several times greater than those of better-known materials like copper and lead. But it is hard to find rare earths, which exist not discretely but mixed with one another in rock, in sufficient concentrations to make mining profitable. One place where they are found in concentration is in Chinese- controlled Inner Mongolia. Another is in the ancient Precambrian igneous rock at Mountain Pass.
Wilson circles wide over the mine site. California's Interstate 15 cuts through the property, gradually climbing to 4700 feet near the mine's entrance before beginning a long, smooth descent toward Las Vegas. We gaze down at the steady line of cars and the brown, empty expanse of the Mojave on either side. Then Wilson aims the helicopter toward the open-pit mine. The rust-orange, stepped excavation is both huge and somehow much smaller than I'd imagined. There is little activity, just a single mining drill on the distant floor and a couple of big puddles reflecting the deep blue of the summer sky. The entire disturbance is about 70 acres at the surface. Just north of the pit is the milling facility, and beyond that, a huge new waste-disposal area the size of several football fields.
The mine, the mill, and the tailings pad are actually a very small part of the total rare-earth production process. "From a capital standpoint, it's only 10 to 15 percent. All the rest of it is a very complex chemical process," says Molycorp's chief technology officer and executive vice president John Burba, a former Dow chemist who developed many of the new processes that make up what Molycorp calls Project Phoenix. "All these elements have close to the same atomic mass and the same ionic charge," Burba explains. As a result, separating the rare-earth elements from one another is an extremely difficult and energy-intensive task requiring dozens of steps. "It takes a lot of chemistry," Burba says. "You use a huge amount of acid and base." Traditionally, the process also generates a lot of dirty, radioactive waste.
The mountain pass deposit was discovered in 1949 by uranium prospectors out with a Geiger counter. Unfortunately for the atomic-age geologists, uranium was in short supply at the site. Instead, their sensor was activated by the radioactive element thorium, which, along with cerium, lanthanum, and most of the other lanthanides, is found at Mountain Pass. Cerium was the first rare-earth element to find a commercial market (lighter flints), though the much rarer euro pium was the deposit's first big earner?the element is used to create the red phosphor in color-TV tubes. And when color TV took off in the early 1960s, europium from the Mojave deposit was being used in nearly every TV set in the world.
By the 1970s and 1980s the deposit was meeting all of the U.S.'s rare-earth needs?and much of the rest of the world's. The California desert operation, which was then owned by Unocal (Union Oil Company of California), employed hundreds of workers, and the separating process produced 850 gallons of salty, radioactive waste water every minute, all of which was piped to gigantic evaporation ponds 14 miles away. It wasn't until the mid-1980s that a serious competitor appeared: China. Within a decade the low labor costs and extensive government subsidies at China's mines had driven global prices into the ground.
Then, in 1996, a breach in a Mountain Pass wastewater pipe spilled 350,000 gallons of radioactive water into the nearby Ivanpah Valley. For the next few years Unocal battled over cleanup with regulators, who belatedly discovered that since the mid-1980s the com pany had recorded?but not reported?dozens of additional spills totaling 971,000 gallons. In 1998 Unocal announced it would suspend operations until environmental reviews were complete. Four years later, the mine closed. In 2005 Chevron acquired Unocal, and three years later sold the Mountain Pass facility to Molycorp.
Tailings disposal has also bedeviled Chinese mines, which have atrocious environmental records. A June 2012 Chinese government white paper blames the reduced export quota in part on a production slowdown that's occurring as authorities address problems, and bluntly reports their scope: "Excessive rare-earth mining has resulted in landslides, clogged rivers, environmental pollution emergencies, and even major accidents and disasters, causing great damage to people's safety and health ..." The Baotou facility in Inner Mongolia is the world's largest rare-earth mine and arguably the worst offender. "They use a very corrosive sulfuric acid system that actually liberates hydrofluoric acid, which is really bad," Burba says. "It is so aggressive it solubilizes everything, including thorium." The Baotou waste is put in a single, enormous holding pond. "Then it leaks into the groundwater," Burba says. "It carries an acidic, metal-laden solution that's also radioactive. So that's the way the Chinese operate."
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