Rhodium, platinum and palladium are part of the platinum group metals (PGMs), primarily used to manufacture automobile emission control devices.

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The idea is that carbon dioxide emission reductions will result as travelers switch from automobile and airlines use.

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Corning's close relationship with Detroit, growing from its business of making automobile headlamps, has led to sales of ceramics for auto-emission-control devices.

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But it believes automobile companies will have to integrate themselves into a transportation system for a high-population, low-emission future.

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