Fear of a shortage of rare-earth metals used in high-tech military and industrial products has spawned global efforts to reopen abandoned mines, including the formidable Mountain Pass Mine in California's Mojave Desert.
Discovered in the 1940s by uranium prospectors, Mountain Pass contains an array of rare earths, including cerium and lanthanum, in concentrations almost double those found at the world's biggest rare-earth mine, China's Bayan Obo.
"You're looking at the greatest rare-earth deposit in the world," says operations manager John Benfield as he ushers a visitor around the 2,200-acre site 60 miles southwest of Las Vegas.
Benfield's employer, Molycorp Minerals in Colorado, has just begun a two-year effort to restore Mountain Pass to its former role as a leading global producer. Those plans were given a boost recently amid fears that China was poised to ban exports of some of the scarcer rare-earth metals and to sharply limit shipments of others.
Although the Chinese government has sought to allay those concerns, a possible ban served as a reminder that the Asian nation is nearly the sole source worldwide for rare-earth metals and is likely to remain so for at least the next two years.
"You always want multiple sources for your raw materials," said Jim Hedrick, commodity specialist with the U.S. Geological Survey. "There could be a natural disaster that significantly disrupts the supply, or there could be geopolitical issues. . . . All it takes is for one person to antagonize another."
The reopening of the mine and related processing facilities would create about 900 jobs at Mountain Pass -- about 100 people work there now -- and provide U.S. companies with a reliable source for many key rare-earth metals.
These minerals, such as samarium and neodymium, are prized for chemical properties that make them indispensable in a variety of industrial and military uses including polishing glass, oil refining and manufacturing missile guidance systems.
They also play a crucial role in the development of "green" technologies such as hybrid cars, wind turbines and compact fluorescent lightbulbs. Heat-resistant magnets made with rare-earth alloys are key components of the electric motor in the Toyota Prius, for example. And lanthanum, one of the most abundant rare earths found at Mountain Pass, is used to make the car's nickel-metal hydride battery.
Mining operations ceased at Mountain Pass in 2002 amid environmental concerns and cut-rate competition from China, though processing of previously dug ore continues.
On a recent Friday, as the weekend traffic flowed on Interstate 15 toward Las Vegas and the temperature hovered around 110, the ore processing facilities hummed with activity. But the crushing mill and the conveyors that fed it with rock from the mine were silent.
The mine itself is about 1,500 feet across -- impressive to the uninitiated but smallish compared with the mile-wide behemoths around the globe where copper, gold and other minerals are excavated.
There's no giant earthmoving equipment rumbling about. Most of it was sold off when the mine was shut down. A small pump floats on the surface of the brackish green water 300 feet below. The only other signs of life in the pit are red-tailed hawks circling the mine's terraced sides in search of lunch.
Molycorp hopes to generate big profit at Mountain Pass by building an integrated manufacturing chain that starts with raw ore and ends with finished products ready for market.
"We don't want to be just a supplier of basic materials to other industries," said Benfield, the operations chief. "We want to develop our own technologies so we can determine our own destiny rather than rely on others. We're not just a mine."
The U.S. was once the world leader in rare-earth metal production. But low-cost competition from China has given that nation a near monopoly on rare-earth exports. In addition, China is becoming a key producer of rare-earth magnets.
That worries some analysts who fret that China could dominate the market for next-generation clean-energy technology in much the same way that a handful of oil-rich nations now control the bulk of world oil supplies. The fact that China and the U.S. are currently engaged in a trade tiff over tire imports hasn't soothed matters.
"They've been reducing exports of rare-earth metals for years," commodities analyst Jack Lifton said. "A few years ago, they exported 50% of their production. Now they're down to 25%. They could be down to zero by 2015 because their own demand is going up."
Rare-earth anxiety has spurred a global hunt for the minerals and is bringing back into production mining operations that have been closed for years, such as Mountain Pass.
Toyota Motor Corp. and other big users of rare-earth metals, such as Hitachi Ltd., are exploring ways to reduce their dependence on Chinese exports. They're using smaller amounts of rare-earth metals, recycling more, testing alternative materials and looking for new sources of supply.
Most of the rare-earth metals aren't all that rare. "Almost any rock you pick up has rare-earth elements in it," noted Thomas Monecke, a geology professor at the Colorado School of Mines.
The most common, cerium, is more plentiful than copper. The two rarest, thulium and lutetium, are 200 times more common than gold.
But unlike coal, iron and other industrially useful minerals, they are difficult to separate and can be mined profitably only when found in dense concentrations, such as at China's Bayan Obo mine and in clay deposits in that country's southern region.
The only other place on earth known to harbor such dense concentrations is Mountain Pass.
Molycorp, a former Chevron Corp. subsidiary, was sold to a group of private equity investors last year. Chevron had acquired the mine when it bought Unocal Corp. in 2005 and is still responsible for cleaning up some wastewater spills from past operations.
The mine's new owners are in the midst of an ambitious plan to pump out the millions of gallons of water at the bottom of the open-pit mine and resume mining by the second half of 2011.
Once ore is again coming out of the ground, Molycorp wants to install advanced extraction processes that will enable the company to achieve purities as high as those found in Chinese rare-earth metals but at a lower cost. They are also looking for joint venture partners to begin producing their own rare-earth magnets.
It will cost $100 million to $400 million to make that plan a reality. Molycorp Chief Executive Mark Smith said the company was exploring a variety of financing options including issuing debt or selling stock.
He also would consider investments from foreign investors, including Chinese.
The goal is to achieve a production rate of 20,000 tons of rare-earth products a year by January 2012, Smith said. That would meet about 20% of global rare-earth demand, based on last year's total worldwide production of around 124,000 tons, he said.
While Mountain Pass prepares to restart mining operations, mining companies are pushing to develop other known rare-earth deposits, such as those in Canada, Brazil and Australia.
The Chinese also are hunting for overseas sources, though worries about the country's control of world supplies is hampering those efforts. A Chinese mining company recently pulled out of a deal to expand its ownership stake in Australian rare-earth miner Lynas Corp. after the Australian government protested.
Although efforts to diversify the world's sources of rare-earth metals are welcomed in many quarters, Lifton notes that, as at Mountain Pass, these new locations won't become significant producers overnight.
"Until then," he said, "we'll just have to tiptoe through the Chinese tulips."
Times staff writer David Pierson in Beijing contributed to this report.