Australian rare-earths prospector Lynas Corp (LYC.AX) has signed a new long-term supply contract with a European consumer, the firm said on Tuesday, amid international concerns that China is curbing rare-earth exports. China has a virtual monopoly on world supplies of rare earths, used in everything from flat screens to defence equipment, and its moves to restrict exports have prompted consumer nations to look for alternative supply sources. Lynas said the new contract, with an unnamed buyer, was a milestone for the company, which plans to start production next year. "Being the first new rare-earths project into production outside China gives Lynas a significant advantage in developing close relationships with the market consumers," Lynas Executive chairman Nick Curtis said in a statement.