Alcoa (AA) reported a sizable "earnings beat" earlier this month. But all's not well in alumi-land. Another aluminum manufacturer -- Century Aluminum (CENX -0.91%) -- has just warned workers and investors that it might be forced to close down its largest aluminum plant in the United States.

Find out why, and find out what other companies could be put at risk by a shutdown in Hawesville, Ky., as Fool contributor Rich Smith explains in the following video.