But Appalachian Power spokeswoman Jeri Matheney said Monday talks between the two companies were stalled.
"I would say the ball is in their court," Matheney said. "We have met with them and we have looked at many different options and ideas, but we don't currently have pending negotiations."
Century rose 12 percent to $7.56 in New York, the most since November 2011.
Aluminum for delivery in three months has dropped 11 percent in the past year on the London Metal Exchange. It climbed 1.1 percent to $1,899 a ton in London today.
Century on April 25 reported first-quarter net income of $8.3 million, its first quarterly profit since 2011.
Switzerland's Glencore International Plc, the world's largest publicly traded commodities supplier, owns 47 percent of Century, according to a March filing from Century.
Alcoa Inc. and Kaiser Aluminum Corp. are the two biggest producers of the metal by market capitalization.
Business editor Jared Hunt contributed.
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