What happened Shares of Century Aluminum (NASDAQ: CENX) plunged nearly 14% by 2:30 p.m. He also said: "Demand remains strong in our core markets in the U.S. and Europe and inventories have been drawn down to post-financial crisis lows. While we continue to see inflationary pressure in energy markets and other key raw materials, our focus on cost discipline and execution leaves us well situated to benefit from historically high aluminum prices."