NEW YORK ( TheStreet) -- Shares of rare earths company Molycorp ( MCP) rose almost 8% Tuesday after President Obama, the European Union and Japan asked the World Trade Organization to help increase China's exports of rare earths. "This case involves something called rare earth materials, which are used by American manufacturers to make high-tech products, like advanced batteries that power everything from hybrid cars to cell phones," Obama said in a speech Tuesday. "We want our companies building those products right here in America , but to do that American manufacturers need to have access to rare earth materials, which China supplies. Now if China would simply let the market work on its own we would have no objections, but their policies currently are preventing that from happening and go against the very rule that China agreed to follow." China produces more than 90% of the world's rare earths. Beijing has quotas for these materials. Shares of Molycorp rose 6.76% in afternoon trading Tuesday to $31.89 on about double the stock's average trading volume of 4.33 million shares. -- Written by Alexandra Zendrian >To contact the writer of this article, click here: Alexandra Zendrian >To submit a news tip, send an email to: email@example.com. >To follow the writer on Twitter, go to Alexandra Zendrian.