About Platinum, Uranium and Other 'Endangered' Metals

We're all familiar with the concept of endangered plant and animal species, but endangered metals? Yes, it turns out, many of the metals that humans rely on for critical technologies are coming up short on the global supply side.

While it's fairly straightforward to estimate how much of different metals we use each year, it's harder to pin down how much more remains available for extraction from the Earth. That's because competition-wary mining companies can be tight-lipped about their reserve estimates.

As people come to realize the vast amounts of natural resources we consume each year, though, more researchers are starting to pay attention to global metal supplies. They say we're putting a growing strain on available resources of the following metals:

Platinum. The precious metal reached a high price of $2,301.50 per ounce earlier this year, although prices have dropped since then. Still, world supplies of platinum aren't expected to be enough to meet demand. Last year's demand reached seven million ounces, but supplies fell short by some 500,000 ounces, according to John Lewins, managing director of Platinum Australia. This year's shortfall is likely to be even higher. Platinum's rising price-tag is being blamed for a trend of catalytic converter thefts: the precious metal is a key component of the emissions control devices on cars.

Indium. You might not be familiar with this soft, light-colored metal, but you'd notice its absence in your life. Indium is used to make, among other things, liquid crystal displays (LCDs) and light emitting diodes (LEDs), key components of devices like computer monitors and television screens. You'll also find indium in cellphones, digital cameras, GPS devices and watches. Because of the skyrocketing global demand for electronics like these, indium prices have increased dramatically since 2000 and a few market-watchers (though not all) warn we could start running out of the metal in a decade or so.

Copper. Like platinum (and oil), copper also reached record-breaking prices earlier this year. The increase in copper costs has spurred an outbreak of thefts around the globe, with thieves nabbing everything from copper-containing historic plaques and grave markers to pipes and electrical wiring. While the Earth still has ample reserves of copper in the ground, population growth and lifestyle improvements could make a serious dent in supplies. A 2006 study from Yale University concluded that, if every person in the world achieved a U.S.-style living standard, the demand for copper would require all the planet's available ore and all the metal already mined.

Zinc. While zinc ranks as Earth's 23rd most abundant element, growing demand could put a pinch on supplies in the next two to three decades, according to some researchers. Zinc is used to galvanize steel and can also be found in everything from batteries and U.S. pennies to paints, sunscreens and vitamin supplements. If everyone in the world lived like those in the U.S. do, global zinc demand would outstrip supply, the 2006 Yale study said.

Gallium. A soft and silvery metal that must be smelted from bauxite and zinc ores, gallium is widely used in LEDs, semiconductors and other electronics. Rising demand for such devices is keeping up the pressure on global supplies.

Tantalum. Used in cellphones, surgical instruments and implant devices like artificial hips, tantalum and its alloys are prized for their high melting points and resistance to corrosion. One estimate says we could deplete our supplies of tantalum in the next 20 to 30 years. The growing demand for tantalum has even been blamed for the 1998-2002 conflict in the Democratic Republic of the Congo, home to the largest tantalum mines in Africa.

Uranium. Switching to more nuclear energy could help us reduce our dependence on oil and natural gas, as well as cut our greenhouse gas emissions. But the uranium that powers nuclear reactors is also a non-renewable resource. The Energy Watch Group predicts that global uranium production will peak between 2030 and 2035. "Even if we take into account that uranium prices will rise dramatically and that this will raise interest in exploiting previously uneconomical uranium mines, our uranium reserves will be fully depleted in 70 years at the latest," energy expert Werner Zittel said when the Energy Watch Group released its most recent report on uranium in late 2006.

What's the best way to deal with strained metal markets? Experts say we need to put greater effort into recapturing and recycling metals from discarded electronics, cars and other items. Finding ways to use less of some metals or switch to more common ores (or plastics) could also help, though some elements like platinum and uranium aren't easily replaced.