Commodities speculators assume the risk that prices of various commodities might go up or down.

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He said a big factor was that only a month before Japan had moved their currency dramatically, and a lot of people borrowed in the Japanese yen to invest in various commodities and instruments.

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Interestingly, Goldman Sachs reiterated various other trading recommendations in the commodities complex.

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Most banking products are rapidly becoming tradable commodities: anyone can sell bonds, issue mortgages or offer various types of savings account.

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The Commonfund, which invests for various nonprofit organizations, says just 15% of the 708 endowments it polled last year held any commodities.

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