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What: Shares of aluminum producer Century Aluminum (Nasdaq: CENX) were hopping today, gaining as much as 11% in intraday trading after a strong fourth-quarter report.

So what: For the quarter, Century announced earnings per share of $0.64 on revenue of $317 million. The reported EPS doesn't appear to be comparable to the $0.23 estimate from Wall Street as it was padded by a $57 million benefit from changes to a retiree medical benefits program. Revenue, however, did top expectations and, with or without the one-time benefit, the company reversed a loss from last year. Though Century's management is cautious due to factors like low levels of activity from developed economies and inflation concerns in faster-growing developing countries, the trends appear to be moving in the right direction as shipments increased versus last year's fourth quarter and prices climbed.

Now what: As noted above, uncertainties about global growth and commodity prices have left the company a bit cautious. Wall Street seems to have a rosier view of the situation though, as current analyst estimates show the company's earnings per share jumping to $1.17 for 2011. Based on revenue multiples, the stock appears to be reasonably priced right now, so the question will be whether the aluminum market can provide a further tailwind for the company's results.

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Fool contributor Matt Koppenheffer does not own shares of any of the companies mentioned. You can check out what Matt is keeping an eye on by visiting his CAPS portfolio, or you can follow Matt on Twitter @KoppTheFool or on his RSS feed. The Fool's disclosure policy prefers dividends over a sharp stick in the eye.