A regulatory filing report by Astenbeck Capital Management LLC had revealed the firm recently bought shares in rare earth metals and uranium mining companies, presumably in a bid to take advantage of the two commodities' foreseen boom.

According to a Form 13F filed with the U.S. Securities and Exchange Commission, Astenbeck purchased a combined value of $246,659 worth of shares of rare earth metals and a combined value of $239,003 worth of shares of uranium, all at the end of September.

The rare earth metals shares were sourced from Toronto-based Avalon Rare Metals Inc. at 41,856 shares, Vancouver-based Rare Elements Resources Ltd. at 17,139 shares and Montreal-based Quest Rare Minerals Ltd. with 21,000 shares.

On the other hand, the uranium shares were from Lewisville, Texas-based Uranium Resources Inc. at 26,445 shares, Littleton, Colorado-based uranium exploring company Ur-Energy Inc. at 65,685 shares, Caspar, Wyoming-based Uranerz Energy Corp. at 39,383 shares, and 39,383 shares in Uranium Energy Corp. based in Corpus Christi, Texas.

Composed of 17 elements, rare earth metals are widely used in manufacturing of batteries of hybrid vehicles, computers, digital cameras, televisions, smartphones, in long-lasting light bulbs and serve as critical magnets in guided missiles.

Uranium is mostly used to power nuclear reactors.

Astenbeck Capital Management LLC is a hedge fund manager formed in February 2010 by Andrew Hall, Phibro LLC's former chief executive officer, and Occidental Petroleum Corporation to manage hedge funds for Phibro's outside investors.

Hall, former Citigroup Inc. energy trader, owns 80 per cent of Astenbeck Capital, with remaining 20 per cent owned by Occidental.

As of end September, the market value of Astenbeck's U.S. equity holdings was at $644 million, according to Bloomberg data.

In an SEC filing, the firm said its Astenbeck Offshore Commodities Fund II raised $2.4 billion from investors as of June 2011.

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