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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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Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Fool's disclosure policy always gets a perfect score.