What: Shares of Century Aluminum Co (CENX -0.91%) jumped as much as 17% on Wednesday after announcing a new debt offering.

So what: Century Aluminum today filed a mixed-shelf offering to sell up to $250 million in debt securities. The debt could help bolster the company's cash position as the aluminum industry deals with low prices and declining margins. 

Broadly speaking, the stock is also trading higher on a big day of gains on Wall Street. As investors get more bullish on the economy, they point to stocks like Century Aluminum as companies that will benefit, and it's climbing along with the rest of the metals industry today.

Now what: I wouldn't read too much into the move today. There are a number of metals stocks that have popped double digits on very little news today, so the gains are widespread. More important for investors will be Thursday's earnings report, when we'll hear how market conditions are affecting Century Aluminum and what management sees for the future. Then it may be time to reassess the struggling metals industry.