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What: Shares of aluminum producer Century Aluminum (Nasdaq: CENX) plunged as low as 12% in early Wednesday trading after the company posted disappointing quarterly results.

So what: Hurt by a big mark-to-market loss on forward contracts and hefty power agreement-related charges, Century Aluminum said it swung to a loss of $16.8 million, or $0.18 a share, in the third quarter. Excluding those items, Century Aluminum's profit came in at $0.04 a share -- still well below the average analyst estimate of $0.08 a share.

Now what: Although high aluminum inventories and a weak North American market remain concerns, strong Chinese demand and stable commodity prices have been positives for Century Aluminum's top line. Despite the bottom-line disappointment, the company's third-quarter revenue of $279.2 million still managed to top estimates. With Alcoa's (NYSE: AA) recent results also indicating that the broad economic trends are, indeed, improving, today's plunge in Century Aluminum may be worth pouncing on.

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