The iPath DJ-UBS Copper Total Return Sub-Index ETN ( JJC) is the most liquid of the exchange traded products that follow copper prices.

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Researchers conclude that a potential future global population of 10 billion people could consume 1.7 trillion kilograms of copper total, greater than the estimated global in-ground stocks of 1.6 trillion kilograms.

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Freeport is first and foremost a copper company: copper contributes 73% to the total reserves, while gold only contribute 5%.

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And though Chile has developed new exports, copper made up 42% of its 1997 total.

ECONOMIST: Chile

Copper has more than doubled as a share of total import value during this time as well.

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