The difference will become even clearer when commodity prices fall and the economic cycle turns.

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But all too often, purchasers fail to negotiate lower prices when commodity prices fall again.

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However, Heath Jansen of Citigroup points out that the best time for diversified firms to take over their more specialised rivals is when commodity prices fall.

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Historically, commodity prices, particularly gold, have been instant indicators when a central bank prints too much money (commodity prices uniformly zoom up) or too little (commodity prices generally fall).

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