PALLADIUM

It’s a lustrous white material, one of the six platinum-group metals. About 85% of palladium ends up in the exhaust systems in cars, where it helps turn toxic pollutants into less-harmful carbon dioxide and water vapor. It is also used in electronics, dentistry and of course jewelry.
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Discovered in 1803 and named after an asteroid, palladium is more rare than gold or platinum. The only palladium mine in the United States is the Stillwater Mine in Montana; other mines are in Canada, South Africa and Russia, the world's largest palladium producer.

Palladium is one of six elements in the platinum group, along with platinum, rhodium, ruthenium, osmium and iridium. These metals are known for being excellent catalysts, or substances that speed up chemical reactions.
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On Aug. 18, 2014, palladium's price hit $900 per troy once, the highest seen since 2001.

Palladium gets its name from Pallas, the second-largest asteroid in the asteroid belt, which had just been discovered in 1802. The asteroid itself was named after the ancient Greek goddess Pallas Athena. (Pallas was visible from Earth in February 2014.)

Palladium is malleable and doesn't tarnish in air, making it a popular metal for jewelry. Since 1989, however, the main use for palladium has been in catalytic converters for automobiles. When a car's internal combustion engine burns fuel, the reaction isn't complete; before catalytic converters were developed, all sorts of nasty compounds escaped through the exhaust pipe, including unburned hydrocarbons and nitrogen oxides.